Stable hydroalcoholic compositions

ABSTRACT

Disclosed is a composition including a lower alcohol and water in a weight ratio of about 35:65 to 100:0, between at least 0.5% and 8.0% by weight thickener system comprised of at least two emulsifiers, each emulsifier present in at least 0.05% by weight wherein the composition free of auxiliary thickeners has a viscosity of at least 4,000 centipoise at 23° C. and wherein each emulsifier is comprised of at least one hydrophobic group and at least one hydrophilic group. The composition is useful as a presurgical scrub replacement, a lotion or other hand preparation.

[0001] This application is a continuation of Ser. No. 09/320,590 filedon May 27, 1999, which is a continuation of Ser. No. 08/781,090, filedon Jan. 9, 1997, which is a continuation-in-part of Application Ser. No.08/493,714, filed Jun. 22, 1995, all of which are incorporated herein byreference.

FIELD OF THE INVENTION

[0002] The present invention relates to compositions useful as skindisinfectants, surgical hand preparations, patient skin preparations andantimicrobial hand lotions. More specifically the invention relates tostable hydroalcoholic compositions which are thickened using mixedemulsifier systems.

BACKGROUND OF THE INVENTION

[0003] Control of nosocomial infection and exposure to infectiousdisease is of paramount concern to doctors, nurses, and clinicians whowork in hospitals and surgery centers. One of the most effective methodsfor controlling infection is regimented hand disinfection before andpossibly after each patient contact and particularly before and aftereach surgical procedure. Hand disinfection is generally accomplishedusing antimicrobial soaps with water. These soaps are usually formulatedto include either povidone-iodine (usually 7.5% by weight) orchlorhexidine gluconate (CHG) (usually 2 or 4% by weight) as the activeantimicrobial agent. In addition, these formulated soaps may containsurfactants and possibly low levels of humectants such as glycerin.

[0004] Hand disinfection is also accomplished using presurgical scrubreplacements. These are used instead of the soap and water scrub.Presurgical scrub replacements ideally achieve bacterial kill equal toor better than a traditional soap and water scrub and in a shorterperiod of time. Additionally, they maintain or improve the skin'snatural barrier to microbial and chemical contamination while providingacceptable tactile properties. Examples of presurgical scrubreplacements include hydroalcoholic gels which generally include highlevels of either ethanol or isopropanol as the disinfecting agent andalso include a thickener and optionally include a humectant (e.g.glycerin). To date, thickeners used in hydroalcoholic gels have beenbased on anionic polymers such as polyacrylic acid (sold under thetradename Carbopol by BF Goodrich Specialty Polymers and ChemicalsDivision of Cleveland, Ohio). U.S. Pat. No. 4,915,934 to Tomlinsondiscloses the use of CHG-containing antiseptic foams based onhydroalcoholic solvents, a fatty alcohol, and a surfactant. Thesurfactant is selected from the group of ethoxylated sorbitan alkylates,ethoxylated fatty alcohols, and ethoxylated nonyl phenols.

[0005] Formulating stable viscous hydroalcoholic emulsions is difficultfor two reasons. First, addition of short chain alcohols (such asethanol) to an aqueous system decreases the surface tensiondramatically. For example, 40% by weight ethanol in water has a surfacetension of approximately 31 dyne/cm compared to pure water which has asurface tension of about 72 dyne/cm at 20° C. A hydroalcoholic solutionat 60% by weight ethanol has a dramatically decreased surface tension ascompared to water. Such a composition has a surface tension ofapproximately 27 dyne/cm at 20° C. Second, many surfactants typicallyused in cosmetic emulsions become completely or partially soluble inhydroalcoholic systems.

[0006] In bulletin 51-0001-259 regarding skin care, Specialty Chemicalsof ICI America of Wilmington, Del. stated that although ethanol canprovide several benefits to skin care emulsions, formulators often avoidethanol as it is difficult to prepare stable emulsions in its presence.In fact, the bulletin continued that ethanol is often used to breakemulsions.

[0007] U.S. Pat. No. 4,956,170 to Lee discloses a hydroalcoholic skinmoisturizing/conditioning antimicrobial gel. The gel comprises 60-75%ethanol and 0.4-2% of a polymeric thickening agent. The formulationsalso comprise polyethoxylated non-ionic surfactants/emulsifiers tostabilize the added emollient oils in addition to a fatty alcohol.

[0008] U.S. Pat. No. 5,167,950 to Lins discloses an antimicrobialaerosol mousse having a high alcohol content. The mousse comprisesalcohol, water, a polymeric gelling agent and a surfactant systemcomprising a C16-C22 alcohol, aerosol propellant and a non-ionicpolyethoxylated surfactant.

SUMMARY OF THE INVENTION

[0009] This invention provides compositions useful as products for skindisinfection such as presurgical hand preps, patient preps, and lotions.The preferred formulations of this invention, in general, have a verynice feel after both single and multiple applications. Additionally,preferred formulations maintain or improve the skin condition aftermultiple applications and no slimy or abnormal feeling is noticed duringpost application hand washing. When used as a presurgical scrubreplacement, this invention achieves bacterial, fungal, and viral killequal to or better than a traditional soap and water scrub in a shorterperiod of time while maintaining or improving the skin's natural barrierto microbial and chemical contaminants. The invention overcomes theshortcomings of past compositions by providing a viscous compositionwhich includes a high concentration of a lower alcohol but does notrequire a polymeric thickener to make the composition viscous. Further,the composition has a cosmetically elegant feel and may be dispensed asa lotion or as a foam.

[0010] This invention provides a composition comprising a lower alcoholand water in a weight ratio of about 35:65 to 100:0, between at least0.5% and 8.0% by weight thickener system comprised of at least twoemulsifiers, each emulsifier present in at least 0.05% by weight whereinthe emulsifiers are selected such that the composition free of auxiliarythickeners has a viscosity of at least 4,000 centipoise at 23 degrees C.and wherein each emulsifier is comprised of at least one hydrophobicgroup and at least one hydrophilic group, wherein: (i) the hydrophobicgroup is comprised of an alkyl group of at least 16 carbon atoms; analkenyl group of at least 16 carbon atoms; or an aralkyl or an aralkenylgroup of at least 20 carbon atoms; and (ii) the hydrophilic group of atleast one emulsifier is comprised of an amide group having the structure—NHC(O)R′″ or —C(O)NHR′″ where R′″ is hydrogen or an alkyl group of 1-10carbon atoms optionally substituted in available positions by N, O, andS atoms; an ester group of short chain alcohols or acids (e.g.,L=—C(O)OR′ or —OC(O)R′ where R′ is C1-C4 branched or straight chainalkyl optionally substituted in available positions by hydroxyl groups);a polyglucoside group having 1-10 glucose units; a polyglycerol estergroup having 1-15 glycerol units, a secondary amine group; a tertiaryamine group; a quaternary amine group; an anionic group such as asulfate, sulfonate, phosphate, phosphonate, or carboxylate group; or azwitterionic group having the formula:

[0011] wherein each R″ is independently hydrogen or an alkyl group(having 1-5 carbon atoms) or alkenyl group (having 2-4 carbon atoms),which alkyl or alkenyl groups are optionally substituted with nitrogen,oxygen, or sulfur atoms, including alkyl or alkenyl carboxyl groups; Qis hydrogen or hydroxyl; x is 1 to 4; and L′ is —CO₂ ⁻,—OP(O)(O⁻)(O⁻M⁺), —(O)P(OR′″)(O)(O⁻) (where R′″ is hydrogen or an alkylgroup of 1-10 carbon atoms optionally substituted in available positionsby N, O, or S atoms), —SO₂O⁻, or —OSO₂O⁻, where M⁺ is a positivelycharged counterion present in a molar ratio necessary to achieve a netneutral charge on the emulsifier and is selected from the group ofhydrogen, sodium, potassium, lithium, ammonium, calcium, magnesium, orN⁺R′₄; as well as combinations of these groups; and (iii) thehydrophilic group of at least one emulsifier is comprised of an alcoholgroup; an ethylene oxide/propylene oxide copolymer group having 2-150moles of ethylene oxide plus propylene oxide per mole of hydrophobe(“R”) and bonded to the hydrophobe through an ether or ester linkage,and optionally terminated by C1-C36 alkyl or C6 to C36 alkaryl ester; anester or ether group of a polyhydric alcohol and their polyalkoxylatedderivatives; an ester or ether of sorbitan or polyalkoxylated sorbitangroup, as well as combinations of these groups. Thus, it will beunderstood by one of skill in the art that the emulsifiers can includecombinations of all “L” hydrophilic groups described herein (e.g., estergroups and amide groups in one molecule).

[0012] This invention further provides a method of preparing a stablehydroalcoholic composition comprising the steps of preparing a thickenersystem comprised of at least two emulsifiers as described above; andcombining a hydroalcoholic solvent with the thickener system at atemperature sufficient to melt said thickener system and in an amountthat provides a composition having between at least about 0.5% and 8.0%by weight thickener system.

[0013] This invention also provides a method of preparing a stablehydroalcoholic composition comprising the steps of: (a) heating athickener system to a temperature sufficient to melt said thickenersystem, wherein the thickener system is comprised of at least twoemulsifiers as described above; (b) combining the thickener system andan aqueous phase, and (c) adding a lower chain alcohol to theaqueous/thickener system combination wherein the alcohol to water weightratio in the composition is between about 35:65 to 100:0 and thethickener system is present in the composition between at least about0.5% and 8.0% by weight. Methods of applying such compositions to skinare also provided.

Definitions

[0014] “Ambient temperature” as used herein refers to the temperaturerange between about 21 and 25 degrees C.

[0015] “Auxiliary thickeners” as used herein refers to additives (otherthan the emulsifiers which comprise the thickener system describedbelow) which increase the viscosity of the solvent phase even in theabsence of the thickener system. Certain auxiliary thickeners may actsynergistically with the thickener system to increase the viscosity ofthe resultant formula. Auxiliary thickeners include but are not limitedto soluble and swellable polymers and associative colloidal thickenerssuch as silica, magnesium aluminum silicate, and the like.

[0016] “Emollient” as used herein refers broadly to materials which arecapable of maintaining or improving the moisture level, compliance, orappearance of the skin when used repeatedly.

[0017] “Emulsifier” as used herein is synonymous with “surfactant” andrefers to molecules comprising hydrophilic (polar) and hydrophobic(non-polar) regions on the same molecule.

[0018] “Emulsion” as used herein refers to a stable dispersion of oneliquid in a second immiscible liquid.

[0019] “Lotion” means liquid or cream, free of any propellant.

[0020] “Melt temperature” (Tm) as used herein refers to the temperatureat which compositions or emulsions of the present invention dramaticallylose viscosity.

[0021] “Polymer” as used herein refers to a natural or syntheticmolecule having repetitive units and a number average molecular weightof at least 20,000.

[0022] “Solvent”, “solvent system” or “hydroalcoholic solvent” as usedherein refer to the alcohol and water combination in the presentinvention.

[0023] “Stable” as used herein refers to a composition that displaysless than or equal to 10% by volume separation after centrifuging at2275× g for 30 minutes at ambient temperature.

[0024] “Surfactant” as used herein is synonymous with “emulsifier,” thedefinition of which is given above.

[0025] “Thickener system” as used herein refers to a combination of atleast two emulsifiers each present in a concentration of at least 0.05%by weight capable of providing a viscosity of at least 4,000 centipoiseat 23° C. to the compositions of the present invention without auxiliarythickeners.

DETAILED DESCRIPTION OF THE INVENTION

[0026] The invention provides a composition comprised of a lower chainalcohol, water, and thickening system. Alcohols used in the presentinvention are first discussed followed by a discussion of thickeningsystems. Ingredients which are optionally added to the composition suchas antimicrobial agents and emollients are then discussed followed by adiscussion of how to prepare compositions of the present invention.

[0027] Alcohol

[0028] The alcohol used in the present invention is a lower hydrocarbonchain alcohol such as a C1-C4 alcohol. In preferred embodiments thealcohol is chosen from ethanol, 2-propanol, or n-propanol, and mostpreferably ethanol. Ethanol is a preferred alcohol since it providesbroad spectrum and quick killing of microbes and has an odor acceptableto consumers such as doctors, nurses and clinicians. The inventionanticipates that a single alcohol may be used or that a blend of two ormore alcohols may comprise the alcohol content of the composition.

[0029] The alcohol to water ratio in the present invention is betweenabout 35:65 and 100:0 by weight. Compositions having alcohol to waterratios within the range 40:60 and 95:5 range ensure an efficaciousimmediate bacterial kill. In a preferred embodiment the alcohol:waterratio is between about 50:50 and 85:15, more preferably between about60:40 and about 75:25, and most preferably the alcohol:water ratio isbetween about 64:36 and 72:28 by weight. Higher alcohol to water ratiosare used in a preferred embodiment for optimum antimicrobial activityand to ensure the composition is fast drying.

[0030] Thickener System

[0031] The thickener system useful in this invention affects thecosmetic attributes of the final composition. Preferably, hand preps andlotions of the invention have the following desirable cosmeticattributes. The composition should not result in excessive clumping ofglove powder beneath powdered surgical gloves and should not affect theintegrity of the glove material. The composition should maintain anacceptable viscosity at 25° C. and preferably up to 35° C. Finally, inmost the preferred embodiments formulations are stable to heat and coolcycles (heating up to 50° C. or higher and cooling to ambienttemperature) as well as freeze/thaw cycles (cooling to −30° C. andwarming to ambient temperature). All of these cosmetic attributes areaffected by the types and amounts of emulsifiers chosen which comprisethe thickener system of the present invention and are discussed below.

[0032] The thickener system of the invention must be compatible with thehydroalcoholic solvent system described above in order to provideacceptable cosmetic properties and appropriate viscosity. Compositionsof this invention have a viscosity of at least about 4,000 cps at 23°C., preferably at least about 10,000 cps, more preferably at least about20,000, even more preferably at least about 50,000 cps, even morepreferably at least about 100,000 cps, and most preferably about 80,000to about 500,000 cps measured using a very low shear viscometer such asBrookfield LVDV-I⁺ viscometer and T spindles with a heliopath adapter.Since the emollient system and other optional ingredients may affect theviscosity (either positively or negatively), the measured viscosity isthat of the final composition without any added auxiliary thickeners.

[0033] The viscosity of the present invention is imparted by a thickenersystem comprised of at least two emulsifiers, and preferably at leasttwo emulsifiers from different classes. In a preferred embodiment atleast one of the emulsifiers is a solid at room temperature comprisingat least one long chain hydrocarbon of at least 16 carbon atoms,preferably at least 18 carbon atoms, and more preferably at least 22carbon atoms. At lower alcohol:water ratios of greater than 6:40 thelong chain hydrocarbon preferably has greater than 22 carbon atoms. Thethickener system of the present invention can be described in terms ofthe number average chain length of greater than about 22 carbon atoms.

[0034] Emulsifiers of this invention are comprised of molecules havinghydrophilic (polar) and hydrophobic (non-polar) regions on the samemolecule and conform to the general structure:

(R)_(a)(L)_(b)

[0035] Where “R” represents a hydrophobic group, “L” represents ahydrophilic group, and “a” and “b” are independently 1 to 4.

[0036] In this invention “R” comprises an alkyl group of at least 16carbon atoms, preferably at least 18 carbon atoms and more preferably atleast 20 carbon atoms and most preferably at least about 22 carbonatoms; alkenyl group of at least 16 carbon atoms, preferably at least 18and most preferably at least 20 carbon atoms; or aralkyl or aralkenylgroup of at least 20 carbon atoms, preferably at least 24 carbon atomsand most preferably at least 26 carbon atoms. In a preferred embodimentR is unbranched.

[0037] In the above formula, “L” represents a hydrophilic group. Forexample, L can include an amide group having the structure —NHC(O)R′″ or—C(O)NHR′″ where R′″ is hydrogen or an alkyl group of 1-10 carbon atomsoptionally substituted in available positions by N, O, and S atoms; anester group of short chain alcohols or acids (e.g., L=—C(O)OR′ or—OC(O)R′ where R′ is C1-C4 branched or straight chain alkyl optionallysubstituted in available positions by hydroxyl groups); a polyglucosidegroup having 1-10 glucose units and more preferably 1-3 glucose units; apolyglycerol ester group having 1-15 glycerol units, preferably 2-12glycerol units, and more preferably 3-10 glycerol units; a secondaryamine group; a tertiary amine group; and a quaternary amine group.

[0038] “L” can also include an anionic group such as a sulfate,sulfonate, phosphate, phosphonate, or carboxylate group, or azwitterionic group having the formula:

[0039] wherein each R″ is independently hydrogen or an alkyl group(having 1-5 carbon atoms) or alkenyl group (having 2-4 carbon atoms),which alkyl or alkenyl groups are optionally substituted with nitrogen,oxygen, or sulfur atoms, including alkyl or alkenyl carboxyl groups; Qis hydrogen or hydroxyl; x is 1 to 4; and L′ is —CO₂ ⁻,—OP(O)(O⁻)(O⁻M⁺), —(O)P(OR′″)(O)(O⁻) (where R′″ is hydrogen or an alkylgroup of 1-10 carbon atoms optionally substituted in available positionsby N, O, or S atoms), —SO₂O⁻, or —OSO₂O⁻, where M⁺ is a positivelycharged counterion present in a molar ratio necessary to achieve a netneutral charge on the emulsifier and is selected from the group ofhydrogen, sodium, potassium, lithium, ammonium, calcium, magnesium, orN⁺ R″₄.

[0040] “L” can also include an alcohol group; a polyhydric alcohol groupsuch as, but not limited to, ethylene glycol, propylene glycol, butyleneglycol, pentaerythrytol, glycerol, and sorbitol; an ethylene oxideand/or propylene oxide group, preferably having 2-150 moles of ethyleneoxide plus propylene oxide per mole of hydrophobe (“R”), which is bondedto the hydrophobe through an ether or ester linkage, and optionallyterminated by C1-C36 alkyl ester, C2-C36 alkenyl ester, or C6 to C36alkaryl ester (i.e., aralkyl ester); an ester or ether group of apolyhydric alcohol and their polyalkoxylated derivatives; an ester orether of sorbitan or polyalkoxylated (i.e., polyalkyleneoxide) sorbitangroup, preferably having 2-150 moles of alkylene oxide per mole ofhydrophobic group; as well as combinations of these groups, e.g., apolyethoxylated polyglucoside group. Thus, it will be understood by oneof skill in the art that the emulsifiers can include combinations of all“L” hydrophilic groups described herein (e.g., ester groups and amidegroups in one molecule).

[0041] The hydrophobic and hydrophilic groups on non-ionic emulsifiersare generally selected to have a hydrophile/lipophile balance (HLB) of 2to 20 and more preferably 4 to 16. Furthermore, the weight average HLBof the thickener system is preferably 4 to 16 and more preferably 8 to12. (For example, a thickener system comprised of 40% by weight of anemulsifier with an HLB of 10 and 60% by weight of an emulsifier with anHLB of 15 has a weight average HLB of 13.)

[0042] The emulsifiers which comprise thickener systems may be chosenfrom a single class of surfactants (e.g., a mixture of chain lengthalkyl polyglucosides) but is preferably a mixture of emulsifier classes.Many commercially available emulsifiers are actually comprised of amixture of chain lengths. For example, some behenyl alcohol ascommercially supplied is actually a mixture of alcohols consisting ofprimarily C22 and C20 fractions but contain detectable levels of C24,C18 and C16 fractions. For this reason, the chain lengths specifiedherein refer to the number average chain length. Furthermore, inmultiple emulsifier thickener systems of the present invention, eachemulsifier must be present in a concentration of at least about 0.05%and more preferably at least about 0. 1% by weight to be considered acomponent of a thickener system. Thickener systems of the presentinvention are capable of achieving high viscosities at relatively lowtotal emulsifier concentrations. The total concentration of emulsifierspresent as a thickener system is generally less than about 8% by weight,preferably less than about 5% by weight, more preferably less than about4% by weight, and most preferably less than about 3% by weight of thetotal composition of the present invention. Typically, the thickenersystem is present in the composition in an amount of at least about 0.5%by weight, based on the total weight of the composition. In the mostpreferred compositions of this invention, the thickener system comprisesbetween about 0.75% by weight to about 5% by weight, more preferablybetween about 1.0% by weight to about 3.5% by weight and most preferablybetween about 1.5% by weight to about 3% by weight of the composition.As used herein an emulsifier is considered part of the thickener systemif its presence in the formula results in an increase in the viscosityof the composition. If a certain emulsifier does not result inincreasing the viscosity of the composition, it is considered anemollient or stabilizer as defined below.

[0043] Preferred compositions of the present invention which aresubstantially free of polymeric thickening agents have a “melttemperature” (Tm). If compositions are heated above this melttemperature, they dramatically lose viscosity. The compositions of thepresent invention preferably have melt temperatures greater than 25° C.in order to maintain a high viscosity at room temperature. Morepreferably the melt temperature is greater than 35° C. in order tomaintain viscosity once applied to the skin. The most preferredformulations have a melt temperature greater than 40° C. in order toallow shipping and handling without refrigeration. Thickener systemsaffect the melt temperature of a given composition. In order to obtain apreferred melt temperature a preferred thickener system includes atleast one emulsifier which is solid at ambient temperature. Preferably,all emulsifiers of a thickener system are solid at ambient temperatureto increase the melt temperature of the resultant composition.

[0044] The structure of emulsifiers in a thickener system affects themelt temperature of the resultant composition. In a preferred embodimentat least one emulsifier in a thickener system is capable of promoting acrystalline structure. Crystallinity is promoted by long straight chainalkyl groups, therefore, at least one emulsifier preferably comprises asaturated straight chain hydrocarbon of at least 16, preferably at least18 and most preferably at least 20 carbon atoms. Certain hydrophilichead groups have been found to particularly promote association andcrystallization. Suitable crystalline emulsifiers include alkylalcohols, alkyl polyglucosides, polyglycerol alkyl esters, C1-C4 estersof alkyl alcohols, C1-C4 esters of alkyl carboxylates, optionallysubstituted alkyl amides, alkyl betaines and alkyl phosphates orphospholipids, alkyl quaternary amines, alkyl amine oxidespolyethoxylated alkyl alcohols and alkyl esters of polyethylene glycol.

[0045] In addition to affecting the melt temperature of a composition,the emulsifier chain length also helps to determine the maximum level ofethanol which can be used in the composition and the concentration ofemulsifiers required in the thickener system. At higher levels ofalcohol, longer chain emulsifiers are required to produce viscous stableemulsions. It is believed that higher levels of alcohol tend to swell orsolubilize the emulsifiers to a greater degree than lower levels ofalcohol. Therefore, as the concentration of ethanol increases the chainlength of the hydrocarbon chains in a thickening system must alsoincrease in order to maintain a melt temperature over 35° C. That is,the amount of lower alcohol in the hydroalcoholic system can affect thechoice of surfactant (i.e., emulsifier), and vice versa. For example, ifthe composition includes a lower alcohol to water ratio in excess ofabout 50:50, the thickener system should include at least one surfactanthaving a number average chain length of at least 16 carbon atoms. If thecomposition includes a lower alcohol to water ratio in excess of about60:40, the thickener system should include at least one surfactanthaving a number average chain length of at least 18 carbon atoms. If thecomposition includes a lower alcohol to water ratio in excess of about64:36, the thickener system should include at least one surfactanthaving a number average chain length of at least 20 carbon atoms.

[0046] For example, systems based on a C16/C18 alkyl polyglucoside(Montanov 68 available from Seppic, Inc. of Fairfield, N.J.) incombination with a C18 polyethoxylate (Brij 76 available from ICI ofWilmington, Del.) in 68:32 ethanol:water have a melt temperature ofapproximately 35° C. Similar systems having C22 hydrocarbon chains havemelt temperatures of 45° C. or higher. In addition, as the chain lengthof the hydrophobic component in the thickener system increases, theamount of emulsifier required to achieve a certain viscosity decreases.For example, the Montanov 68 (C16/C18 alkyl polyglucoside)/Brij 76(polyethoxylated C18 alcohol) thickener system requires approximately 5%total emulsifier to achieve a suitable viscosity. A similar system basedon C22 hydrophobes achieves a suitable viscosity at only 2% totalemulsifier.

[0047] The nature and size of hydrophilic head groups of emulsifiers areimportant and help to determine which thickening systems produce viscousstable systems. Certain combinations of emulsifiers will produce viscousstable emulsions. Without being bound by theory, it is believed that thesize, charge, and degree of hydrogen bonding are important parameters todetermine how emulsifiers interact.

[0048] Many preferred thickener systems are capable of producingviscoelastic compositions which are very stable. By varying the ratio ofemulsifiers, the degree of elasticity can be adjusted from almost apurely viscous composition to a highly elastic and even stringycomposition. If emollients are added, increasing the elasticity of thesystem imparts added stability to prevent separation of immiscibleemollients. Excessive elasticity, however, is not preferred since anelastic composition usually does not provide a cosmetically appealingproduct. Addition of certain emulsifiers with at least two hydrophobiccomponents has been shown to limit the viscoelasticity while ensuringviscous stable compositions. A favored class of multiple hydrophobiccomponent emulsifiers are quaternary ammonium salts conformingsubstantially to the following structure:

[0049] where:

[0050] R′ and R″ are long chain alkyl or alkenyl hydrocarbon chains ofat least 16 carbon atoms;

[0051] R′″ is a short chain alkyl group of 1 to 4 carbon atoms,preferably methyl or ethyl;

[0052] R″″ is equivalent to either R′ or R′″ and is preferablyequivalent to R′″; and

[0053] X is a halogen, R′″SO₃ ^(⁻) , R′″SO₄ ^(⁻) , or R′″CO₂ ^(⁻)

[0054] Some preferred structures include distearyldimethylammoniumchloride, dibehenyldimethylammonium chloride, anddibehenyldimethylammonium methosulfate, while dibehenyldimethylammoniummethosulfate is a more preferred structure. Other suitable multiplehydrophobic emulsifiers include dialkylglycerol esters, trialkylglycerolesters, polyglycerol alkyl esters, ethylene glycol dialkylesters,polyethylene glycol dialkylesters, dialkylamides of diamines such asethylene diamine, polyalkylesters of pentaerythritol and dialkyl(optionally ethoxylated) phosphates, and alkyl esters ofpolyethyoxylated alkyl alcohols.

[0055] The following emulsifier classes are offered as nonlimitingexamples of suitable emulsifiers for use in the present invention.Examples of some preferred emulsifiers are provided for each emulsifierclass. For the present invention an emulsifier must be present with atleast one coemulsifier to provide a thickener system to produce stableviscous compositions.

[0056] Class 1. Alkyl or Alkenyl Polyglucosides:

[0057] where R is a straight chain alkyl or alkenyl group of at least 16carbon atoms, preferably at least 18 carbon atoms, and most preferablyat least 20 carbon atoms; or an aralkyl or aralkenyl group of at least22 carbon atoms, preferably at least 24 carbon atoms and most preferablyat least 26 carbon atoms; and n=0-10 (when n=0, the valence of theoxygen atom is completed by H), preferably 1-5 and more preferably 1-3.

[0058] Nonlimiting examples of preferred alkyl or alkenyl polyglucosideemulsifiers include cetearyl glucoside sold as “MONTANOV” 68 by Seppic,Inc. of Fairfield, N.J.; behenyl glucoside, produced experimentally as“ESSAI 624” MP, an alkyl polyglucoside prepared with 92% C-22 alcoholand corn-derived glucoside by Seppic, Inc.; and oleyl glucoside.

[0059] Class 2. Short Chain Esters of Long Chain Alcohols or Acids:

RC(O)OR′ or ROC(O)R′

[0060] where R is as defined immediately above for Emulsifier Class 1;and R′ is C1-C4 branched or straight chain alkyl group, optionallysubstituted in available positions by hydroxyl groups.

[0061] Some preferred short chain esters of long chain alcohols or acidsinclude but are not limited to methyl behenate sold as “KEMESTER 9022”by Witco, Humko Chemical Division of Memphis, Tenn.; methyl stearatesold as “KEMESTER 4516” by Witco; methyl oleate sold as “KEMESTER 205”by Witco; arachidyl proprionate available as “WAXENOL 801” from Alzo ofSayreville, N.J.; behenyl lactate, stearyl acetate; and glycerolmonoerucate available from Croda, Inc. of Parsippany, N.J.

[0062] Class 3. Alkyl and Alkenyl Alcohols:

R₆—OH

[0063] where R₆ is a straight or branched chain alkyl or alkenylhydrocarbon chain of at least 16 carbon atoms, preferably at least 18,more preferably at least 20 carbon atoms, and most preferably at least22 carbon atoms, optionally substituted in available positions by N, O,or S atoms; or an aralkyl or aralkenyl group of at least 22 carbonatoms, preferably at least 24 carbon atoms and most preferably at least26 carbon atoms optionally substituted in available positions by N, O,and S atoms.

[0064] Nonlimiting examples of preferred alkyl and alkenyl alcoholemulsifiers useful in a thickener system of the invention includestearyl alcohol available as “LANETTE 18” from Henkel's Emery Divisionof Cincinnati, Ohio; behenyl alcohol available as “LANETTE 22” fromHenkel; oleyl alcohol available as “NOVOL” from Croda; C-24 alcoholavailable as “UNILIN 350” from Petrolite of Tulsa, Okla.; C31 alcoholavailable as “UNILIN 425” from Petrolite; and arachidyl alcoholavailable as “AR-20” from M. Michel and Co. of New York, N.Y.

[0065] 4. Polyglycerol Ester

[0066] where each R₁ is independently hydrogen or a straight chain alkylgroup of at least 16 carbon atoms, preferably at least 18 and morepreferably at least 20 carbon atoms; or an aralkyl or aralkenyl group ofat least 22 carbon atoms, preferably at least 24 carbon atoms, and mostpreferably at least 26 carbon atoms; and n=0 to 15, preferably 1 to 12,and most preferably 2 to 10.

[0067] Some examples of preferred polyglycerol ester emulsifiers usefulin a thickener system of the present invention include but are notlimited to decaglycerol monostearate available as “POLYALDO 10-1-S” fromLonza Inc. of Fairlawn, N.J.; tetraglycerol monostearate available as“TETRAGLYN 1-S” from Barnet Products Corporation of Englewood Cliffs,N.J.; and decaglyceroltetrabehenate.

[0068] Class 5. Quaternary Amine

[0069] where R is as defined above in Emulsifier Class 1; R₂ is the sameas R₃ or a long chain alkyl or alkenyl hydrocarbon chain of at least 16carbon atoms, preferably at least 18 and more preferably at least 20carbon atoms optionally substituted in available positions by N, O, andS; or an aralkyl or aralkenyl group of at least 22 carbon atoms,preferably at least 24 carbon atoms, and most preferably at least 26carbon atoms;

[0070] R₃ is a short chain alkyl group of 1 to 4 carbon atoms,preferably methyl or ethyl;

[0071] R₄ is equivalent to either R₂ or R₃ and is preferably equivalentto R₃; and

[0072] X is a halogen, R₅SO₃ ^(⁻) , R₅SO₄ ⁻, R₅CO₂ ⁻, (R₅)₂PO₄ ⁻, or(R₅)PO₄ ^(₌) ; where R₅ is defined in Class 6 below.

[0073] Nonlimiting examples of quaternary amine emulsifiers includedibehenyldimethylammonium methosulfate available as “INCORQUAT DBM-90”from Croda; behenyltrimethylammonium chloride available as “NIKKOLCA-2580” from Barnet; and tallowtrimethylammonium chloride available as“ARQUAD T-27W” from Akzo Chemicals, Inc. of Chicago, Ill.

[0074] Class 6. Tertiary Amine and its Protonated Salts

[0075] where R, R₂, and R₃ are as defined above in Class 5 and R₂ and R₃may also be selected from polyethoxylated or polyproxylated alkyl oralkenyl alcohol chains having 1-50 moles of ethylene oxide or propyleneoxide groups per mole of emulsifier and Y is a halogen, R₅SO₃ ^(⁻) ,R₅SO₄ ^(⁻) , R₅CO₂ ^(⁻) , (R₅)PO₄ ⁻, or (R₅)PO₄ ^(₌) , where R₅ is analkyl or alkenyl group of 1-22 carbon atoms optionally substituted inavailable positions by N, O, and S.

[0076] Some examples of emulsifiers from the class of tertiary aminesand their protonated salts useful in a thickener system of the inventioninclude but are not limited to behenamidopropyldimethylamine availableas “INCROMINE BB” from Croda; behenamidopropyldimethylamine gluconate;tallowdimethylamine hydrochloride; dihydrogenated tallow methyl amine;stearyl diethanolamine hydrochloride; polyethoxylated stearyldiethanolamine hydrochloride.

[0077] Class 7. Amine Oxides

[0078] where R₂ and R₃ are as defined above for Class 6 and R₆ is asdefined above for Class 3.

[0079] Nonlimiting examples of emulsifiers from the class of amineoxides suitable in a thickener system of the invention includebehenamine oxide (behenyldimethylamine oxide) available as “INCROMINEB-30P” from Croda; stearamine oxide available as “INCROMINE Oxide S”from Croda; behenamidopropyldimethyl amine oxide; andbis(2-hydroxyethyl)tallow amine oxide available as “AROMOX T/12” fromAkzo.

[0080] Class 8. Polyethoxylated and/or Polypropoxylated Alcohols andEsters and Derivatives thereof

[0081] where R₆ is as defined above for Emulsifier Class 3; m=0-200,preferably 2-50, most preferably 4-20;

[0082] p=0 or 1;

[0083] R₈=H or —C(O)—R₁₂, where R₁₂ is an alkyl or alkenyl group of 1-36carbon atoms optionally substituted by N, O or S, or an aralkyl group of6 to 36 carbon atoms; and

[0084] r=0-50.

[0085] Some examples of preferred emulsifiers from the class ofpolyethoxylated alcohols and esters include but are not limited tosteareth-2 available as “BRIJ 72” from ICI Americas Inc. of Wilmington,Del.; steareth-10 available as “BRU 76” from ICI; beheneth-5 availableas “NIKKOL BB-5” from Barnet Products Inc.; beheneth-10 available as“NIKKOL BB-10” from Barnet; C31 alkyl-10EO available as “UNITHOX 450”from Petrolite Corp. of Tulsa, Okla.; C31 alkyl-40 EO available as“UNITHOX 480” from Petrolite, and the lauric ester of “UNITHOX 480”available from Petrolite as X-5171.

[0086] Class 9. Zwitterionics:

[0087] wherein R is as defined above for Emulsifier Class 1; each R₇ isindependently hydrogen or an alkyl group (having 1-5 carbon atoms) oralkenyl group (having 2-4 carbon atoms), which alkyl or alkenyl groupsare optionally substituted with nitrogen, oxygen, or sulfur atoms,including alkyl or alkenyl carboxyl groups; Q is hydrogen or hydroxyl; xis 1 to 4; and L′ is —CO₂ ⁻, —OP(O)(O⁻)(O⁻M⁺), —(O)P(OR′″(O)(O⁻M⁺)(where R′″ is hydrogen or an alkyl group of 1-10 carbon atoms optionallysubstituted in available positions by N, O, or S atoms) —SO₂O⁻, or—OSO₂O⁻, where M⁺ is a positively charged counterion present in a molarratio necessary to achieve a net neutral charge on the emulsifier and isselected from the group of hydrogen, sodium, potassium, lithium,ammonium, calcium, magnesium, or N⁺R′₄ where each R′ is independently analkyl group of 1 to 4 carbon atoms optionally substituted with N, O, orS atoms.

[0088] Nonlimiting examples of emulsifiers from the class of zwitterionsuseful in the emulsifier system of the invention includestearamidopropylPG-dimmonium chloride phosphate available as“PHOSPHOLIPID SV” from Mona Industries of Paterson, N.J.; and behenylbetaine available as “INCRONAM B-40” from Croda.

[0089] Class 10. Alkyl and Alkenyl Amides:

[0090] where R₆, R₇, and R₁₂ are as defined above in Classes 3, 9, and 8respectively.

[0091] Examples of some preferred emulsifiers from the class of alkyland alkenyl amides useful in a thickener system of the invention includebut are not limited to behenamide available as “KEMAMIDE B” from Witco;stearamide available as “UNIWAX 1750” from Petrolite;Behenamidopropyldimethyl amine available as “INCROMINE BB” from Croda;stearyldiethanolamide available as “LIPAMIDE S” from Lipo Chemicals Inc.of Paterson, N.J.; and Erucamide available as “ARMID E” from Akzo.

[0092] Class 11. Esters and Ethers of Polyhydric Alcohols

[0093] wherein t=0-4; each R₉ is independently chosen from H, —CH₂OR₁₀,—OH, or a hydrocarbon chain of 1 to 4 carbon atoms, preferablycontaining 1 carbon atom; s=0 or 1; wherein R₁₀=H or R₁₂wherein R₁₂ isas defined above for Emulsifier Class 8.

[0094] Examples of esters and ethers include glycerol monobehenate,pentaerythritol distearate and glycerol tribehenate.

[0095] Esters and ethers of polyethoxylated polyhydric alcohols are alsouseful. For example, these include but are not limited topolyethoxylated glycerol monostearate, polyethoxylated penta erythritolbehenate, polyethoxylated propylene glycol monostearate.

[0096] Class 12. Anionics

[(R₁₄)_(a)L^(−c) _(d)](M^(+b))_(e)

[0097] Where R₁₄ is an alkyl, alkenyl, or aralky group of at least 16carbon atoms, preferably at least 18 carbon atoms and most preferably atleast 20 carbon atoms optionally comprising oxygen, nitrogen, or sulfuratoms within or substituted upon the alkyl or alkenyl chain; or apolyethoxylated and/or polypropoxylated alkyl, alkenyl or aralkyl group,which alkyl, alkenyl, or aralkyl group comprises at least 16 carbonatoms, preferably at least 18 carbon atoms and most preferably at least20 carbon atoms optionally comprising oxygen, nitrogen, or sulfur atomswithin or substituted upon the alkyl, alkenyl, or aralkyl chain. WhenR₁₄ comprises a polyethoxylated or polypropoxylated substituent or acopolymeric substituent of ethylene oxide and propylene oxide, thesesubunits are present in amounts of 1 to 100 moles, preferably 1 to 20moles per mole of hydrophobe; L is sulfate (—OSO₂O⁻), sulfonate(—SO₂O⁻), phosphate ((—O)₂P(O)O⁻ or —OP(O)(O⁻)₂), or carboxylate (—CO₂⁻); M is hydrogen (H⁺), sodium (Na⁺), potassium (K⁺), lithium (Li⁺),ammonium (NH₄ ⁺), calcium (Ca⁺²), magnesium (Mg⁺²), or R″A⁺, wherein R″is hydrogen or an alkyl or cycloalkyl group of about 1 to 10 carbonatoms, and A⁺ is selected from the group consisting of N⁺(R)₃ (e.g.,R″A⁺ can be N⁺(CH₃R)₄, HN⁺(CH₂CH₂OH)₃, H₂N(CH₂CH₂OH)₂) or a heterocyclic—N⁺B wherein B comprises 3 to 7 atoms selected from the group consistingof carbon, nitrogen, sulfur and oxygen atoms which complete thenitrogen-containing heterocyclic ring and satisfy the valence on thenitrogen atom; and wherein R is the same as R″ and may also besubstituted in available positions with oxygen, nitrogen or sulfuratoms;

[0098] a and c are independently 1 or 2;

[0099] b and d are independently 1, 2 or 3; and

[0100] e is equal to (c times d)/b.

[0101] Nonlimiting examples of preferred emulsifiers from the anionicclass of emulsifiers suitable for use in a thickener system of theinvention include behenic acid available as Croacid B from Croda, Inc.;stearyl phosphate available as Sippostat 0018 from Specialty IndustrialProducts, Inc. of Spartanburg, S.C.; and sodium stearate available fromWitco.

[0102] Class 13. Sorbitan Fatty Acid Esters

[0103] where R₆ is as defined above in Emulsifier Class 3, R₁₃ is H or—C(O)R₆ and each v is independently 0-30.

[0104] Fatty acid esters of sorbitan and its polyethoxylatedderivatives, polyoxyethylene derivatives of mono and poly-fatty estersare also examples of additional emulsifiers useful in the presentinvention.

[0105] Certain combinations of the above-listed emulsifiers are usefulin some preferred embodiments to form viscous stable thickener systemsof the present invention. These preferred systems are listed below.Nonlimiting Examples of Suitable Thick Systems: System # Emulsifier1/(Class)* Emulsifier 2/(Class)* Emulsifier 3/(Class)* Emulsifier4/(Class)* 1 alkyl polyglucoside (1) polyethoxylated alkyl alcohol (8)quaternary amine (5) 2 alkyl polyglucoside (1) polyethoxylated alkylalcohol (8) amine Oxide (7) 3 alkyl polyglucoside (1) tertiary amine (6)4 alkyl polyglucoside (1) quaternary amine (5) 5 polyglycerol ester (4)polyethoxylated alkyl alcohol (8) alkyl alcohol (3) 6 polyglycerol ester(4) polyethoxylated alkyl alcohol (8) alkyl alcohol (3) alkyl ester (2)7 polyglycerol ester (4) polyethoxylated alkyl alcohol (8) quaternaryamine (5) 8 polyglycerol ester (4) alkyl ester (2) quaternary amine (5)9 polyglycerol ester (4) amine oxide (7) quaternary amine (5) 10alkyl/alkenyl alcohol (3) alkyl ester (2) quaternary amine (5) 11alkyl/alkenyl alcohol (3) alkyl ester (2) amine oxide (7) 12 alkyl ester(2) polyethoxylated alkyl alcohol (8) quaternary amine (5) 13 alkylbetaine (7) polyethoxylated alkyl alcohol (8) 14 alkyl phospholipid (9)polyethoxylated alkyl alcohol (8) 15 alkyl ester (2) alkyl alcohol (3)dialkoxydimethicone 16 hydroxyfunctional polyethoxylated alcohol (8)ester (2) 17 hydroxyfunctional alkyl alcohol (3) quaternary amine (5)ester (2) 18 hydroxyfunctional quaternary amine (5) ester (2) 19polyglycerol ester (4) polyethoxylated alkyl alcohol (8) 20 alkylcarboxylate (12) polyethoxylated alkyl alcohol (8)

[0106] It is a simple matter to test certain combinations of emulsifiersto determine if they provide a suitable thickener system. Screeningmethodology is set forth in the Examples. The examples illustrate theimportance of the head group size with respect to the ratio of the mixedemulsifiers required to produce a stable emulsion. For example, systemsbased on a C16/C18 alkyl polyglucoside combined with C18 polyethoxylatesof varying level of ethoxylation (Brij) produce stable emulsions atwidely varying ratios.

[0107] Without intending to be bound by theory, the physical structureof the composition of the invention is believed to be that of anemulsion. A classic definition of an emulsion is a stable dispersion ofone liquid in a second immiscible liquid. However, as stated earlier,the present composition is preferably formed using at least oneemulsifier which is a wax at room temperature. Although compositions ofthe present invention are not well characterized, they are believed tobe a viscous stable mixture of a solid, semisolid, or liquid phase in asecond liquid phase. It is believed that if certain hydrophobicemollients are added to the present invention, hydrophobic emulsifiersand immiscible emollients form an “oil” or hydrophobic phase which isdispersed in the hydroalcoholic liquid phase to form an “oil” in “water”emulsion. The hydroalcoholic phase is referred to herein as the “water”phase. Since many preferred emulsions are somewhat viscoelastic, theseemulsions are believed to be liquid crystalline emulsions which havebeen cooled below the crystallization temperatures of the chosenemulsifiers to form a semi-crystalline gel-like network. Certainformulations may be simply swollen crystalline precipitates forming astrongly interacting network in the hydroalcoholic phase (so calledcoagel phase). The compositions of the present invention may also existas combinations of these structures. Liquid crystalline and coagelphases in aqueous systems are described in “Application of EmulsionStability Theories to Mobile and Semisolid O/W Emulsions,” Cosmetics andToiletries, Vol. 101, pp 73-92 (1986), and “Influence of Long ChainAlcohols (or Acids) and Surfactants on the Stability and Consistenciesof Cosmetic Lotions and Creams,” Cosmetics and Toiletries, Vol. 92, pp.21-28 (1977) both of which are hereby incorporated by reference. Theexact type of molecular association that occurs depends on many factorsincluding the nature, size, and physical and chemical states of thepolar and hydrocarbon portions of the emulsifiers which comprise thethickener system at a specified temperature.

[0108] Emulsifiers other than those required in the composition toprovide a thickener system may also be added as emollients orstabilizers. These emulsifiers are referred to herein as auxiliaryemulsifiers. For example, certain emollients are also comprised ofhydrophobic and hydrophilic regions and are useful in the presentinvention since they are believed to become incorporated into the liquidcrystalline network. These emollients tend to enhance the stability ofthe composition as is discussed more fully below. Furthermore, certaindimethicone copolyol surfactants can actually improve the stability offormulations incorporating emollients. This is also discussed in moredetail below.

Optional Ingredients

[0109] In addition to alcohol, water and thickener system, thecompositions of the present invention may optionally include ingredientssuch as salts, emollients, stabilizers, antimicrobials, fragrances,therapeutic agents, propellants and additional emulsifiers. Each ofthese optional ingredients along with the effect each has upon theproperties of the final composition is discussed below.

[0110] Salts

[0111] The melt temperature of the compositions of the present inventionmay be increased by adding salts. As the concentration of salt isincreased, the ratio of emulsifiers will often need to change in orderto maintain a stable composition. It is important to choose salts whichdo not create an unstable system and are compatible with anyantimicrobials present in the system. For example, chlorhexidinedigluconate (CHG) will precipitate rapidly in the presence of halidesalts above a concentration of about 0.1M. Therefore, if a systemincludes CHG, preferably gluconate salts such as triethanolaminegluconate or sodium gluconate, are used.

[0112] Stabilizers

[0113] A stable composition is one which does not separate more than 10%by volume after centrifuging at 2275× g for 30 minutes as measured atthe longitudinal midpoint of the sample tube. It is also recognized thatstability may be time dependent due to crystallization of emulsifiersand/or emollients present in the system, coalescence of emollients,emulsifiers and the like and, therefore, preferred compositions do notexhibit separation of more than 10% after standing for 6 months atambient conditions. Two types of stabilizers are useful in the presentinvention. These include (1) those stabilizers that complex withemulsifier hydrophilic head groups, and (2) those that associate withthe emulsifier hydrophobic tails. Certain stabilizers may perform bothfunctions. For example, emulsifiers comprising 1,2 diol-containing headgroups such as alkylpolyglucosides, monoalkylglycerides, andpolyglycerol alkyl esters, may be “stabilized” by adding borate ion.Without intending to be bound by theory, it is believed that borate ionscomplex with adjacent head groups which may increase the association ofhydrophobic tails by holding them in close proximity. Natural orsynthetic polymers comprised of pendent long chain alkyl groups (greaterthan 12 and preferably greater than 16 carbon atoms) such as stearylmodified cellulose derivatives, stearyl modified proteins such as wheatprotein, stearyl modified collagen and the like are capable ofstabilizing compositions of the present invention. Such added componentsmay also increase the melt temperature of compositions of the presentinvention. It is believed that the pendent alkyl groups in thesepolymers associate by Van der Waals interactions with the hydrophobes ofa thickening system, thereby enhancing the stability of the crystallinestructure. Polymeric thickeners which do not have associative pendentalkyl chains may also increase the melt temperature presumably byincreasing the viscosity of the continuous phase. A nonlimiting exampleof such thickeners are quaternary celluloses such as Celquat™ 230M asavailable from National Starch of Bridgewater, N.J. In a preferredembodiment stearyldimonium hydroxypropyl cellulose commerciallyavailable as Crodacel QS from Croda Inc., Parsippany, N.J. is added as astabilizer.

[0114] Emollients

[0115] Emollients are typically added to hand lotions or hand prepsbecause they act to increase the moisture content of the stratumcorneum. Emollients are generally separated into two broad classes basedon their function. The first class of emollients function by forming anocclusive barrier to prevent water evaporation from the stratum corneum.The second class of emollients penetrate into the stratum corneum andphysically bind water to prevent evaporation. The first class ofemollients is subdivided into compounds which are waxes at roomtemperature and compounds which are liquid oils. The second class ofemollients includes those which are water soluble and are often referredto as humectants.

[0116] For the purposes of this invention the thickener system isconsidered separate and distinct from any emollients which may be addedeven though it is recognized that the emulsifiers may function asocclusive emollients and aid in maintaining or improving the skincondition. Emollients are included in a preferred embodiment of theinvention and preferably comprise between about 3 and 30%, morepreferably between about 4 and 20% and most preferably between about 5and 12% by weight of the formulation.

[0117] The ratio of wax to liquid emollients (oils and humectants) in apreferred embodiment of the invention is between about 5:1 to 1:5 andpreferably between about 1:3 to 3:1. Also, the ratio of wax emollientsand wax emulsifiers to liquid emollients and liquid emulsifiers in apreferred embodiment of this invention is from about 1:5 to about 5:1,and more preferably, from about 1:3 to about 3:1. Emollients may beselected from any of the classes known in the art. A general list ofuseful emollients appears in U.S. Pat. No. 4,478,853 and EPO patentapplication 0 522 624 A1 and in the CTFA Cosmetic Ingredient Handbookpublished by The Cosmetic, Toiletry, and Fragrance Association, Wash.D.C. (1992) under the listings “Skin Conditioning agents,” “emollients,”“humectants,” “miscellaneous” and “occlusive,” each of these referencesis hereby incorporated by reference.

[0118] In preferred embodiments, emollients are chosen from thefollowing nonlimiting list of general emollients, occlusive emollientsand humectants. Examples of general emollients include short chain alkylor aryl esters (C1-C6) of long chain straight or branched chain alkyl oralkenyl alcohols or acids (C8-C36) and their polyethoxylatedderivatives; short chain alkyl or aryl esters (C1-C6) of C4-C12 diacidsor diols optionally substituted in available positions by —OH; alkyl oraryl C1-C9 esters of glycerol, pentaerythritol, ethylene glycol,propylene glycol, as well as polyethoxylated derivatives of these andpolyethylene glycol; C12-C22 alkyl esters or ethers of polypropyleneglycol; C12-C22 alkyl esters or ethers of polypropyleneglycol/polyethylene glycol copolymer; and polyether polysiloxanecopolymers. In addition to many of the emulsifiers of preferredthickener systems, additional examples of occlusive emollients includecyclic dimethicones, polydialkylsiloxanes, polyaryl/alkylsiloxanes, longchain (C8-C36) alkyl and alkenyl esters of long straight or branchedchain alkyl or alkenyl alcohols or acids; long chain (C8-C36) alkyl andalkenyl amides of long straight or branched chain (C8-C36) alkyl oralkenyl amines or acids; hydrocarbons including straight and branchedchain alkanes and alkenes such as squalene, squalane, and mineral oil;polysiloxane polyalkylene copolymers, dialkoxy dimethyl polysiloxanes,short chain alkyl or aryl esters (C1-C6) of C12-C22 diacids or diolsoptionally substituted in available positions by OH; and C12-C22 alkyland alkenyl alcohols. Nonlimiting examples of preferred humectant typeemollients include glycerol, propylene glycol, dipropylene glycol,polypropylene glycol, polyethylene glycol, sorbitol, pantothenol,gluconic acid salts and the like.

[0119] Although a thickener system is responsible for the stability andoverall consistency of compositions of the present invention, emollientsmay also affect the viscosity, stability, and melt temperature of acomposition. It is anticipated that a single emollient may be added tothe present invention or two or more emollients may be added to thecomposition. A wide range of emollients may be added to the formulationsof the present invention. Preferably wax and oil type emollients alongwith water soluble emollients are used. In a preferred embodiment,emollient systems are comprised of humectants in addition to occlusivewax and oil emollients in concentrations which achieve a moisturizingbut not greasy composition which maintains and improves the condition ofthe skin upon repeated use. Ideally, emollients are non-comedogenic andare chosen to ensure no skin irritation or sensitization reactionoccurs. This is particularly critical since the composition of thepresent invention will likely be worn in an occluded condition undersurgical gloves. Furthermore, emollients should be chosen which do notaffect the integrity of the glove material. For example, sincehydrocarbon emollients such as mineral oil and petrolatum candetrimentally affect the tear strength of surgical gloves, theseemollients may need to be avoided for compositions employed aspresurgical disinfectants.

[0120] Without being bound or limited by theory, it is believed that ifemollients are added to the present compositions, they may be present infour distinct regions. The emollients could occur (1) as a solublespecies in the solvent phase, (2) dispersed as emulsified dropletswithin the mixed emulsifier micelle or crystalline gel network, (3)incorporated into the mixed emulsifier micelle or crystalline gelnetwork, or (4) as a separate and distinct emulsion. As earlier stated,emollients can affect the melt temperature of a composition. Thoseemollients that are soluble or dispersible in the solvent phase tend tohave little or no affect on the melt temperature and are thereforepreferred. These emollients include the humectant and generalemollients. The most preferred general emollients are those which areessentially insoluble in water but soluble in the hydroalcoholicsolvent. These emollients are also preferred since they remain solubleand uniformly dispersed even above the melt temperature so that uponcooling to room temperature a uniform composition results. In addition,they are also believed to have little effect on surgical gloves. Suchgeneral emollients typically do not have alkyl or alkenyl chains greaterthan about 14, preferably not greater than 12 and most preferably notgreater than about 9 carbon atoms.

[0121] Those emollients which are insoluble in the hydroalcoholicsolvent may associate with the emulsifiers of the thickener systemand/or become incorporated into the micelle or crystalline gel network.Preferred emollients within this class are those emollients that arevery hydrophobic since they tend to maintain a high melt temperature.For example, hexadecane was found to increase the viscoelasticity ofcertain thickener systems. Those emollients which are capable ofassociating with and disrupting the emulsifiers of the thickener systemtend to decrease the melt temperature and may influence the stability ofthe composition. Certain branch alkyl esters of greater than about 12carbon atoms per hydrophobe have been found to be particularly effectiveat decreasing the melt temperature. For example, trioctyldodecyl citratehas been found to significantly decrease the melt temperature of somesystems.

[0122] Emollients which become incorporated into the thickener systemtend to decrease the melt temperature. For example, laureth-4 (Brij 30)appears to incorporate into the thickener system since it does not phaseout when heated above the melt temperature at concentrations below about1% by weight. Laureth-4 also tends to decrease the melt temperature ofthe composition.

[0123] Certain emollients which are insoluble in the hydroalcoholicsolvent can be emulsified in what is believed to be a separate anddistinct emulsion. These emollients have little affect on the melttemperature of a composition. For example, certain cyclic silicones,polysiloxanes, and dialkoxypolysiloxanes can be emulsified inhydroalcoholic solvents using polyether/polysiloxane copolymerssurfactants. Cyclic silicones such as DC344 (available from Dow Comingof Midland, Mich.) in the presence of certain polyether/polysiloxanecopolymers such as Abil B88183 available from Goldschmidt Chemical Corp.of Hopewell, Va., can form a thermally stable emulsion such that thecompositions remain uniform both above and below the melt temperature.In fact, the combination of a long chain dialkoxypolysiloxane andpolyether/polysiloxane copolymer has been found to actually promote thestability of certain thickener systems. The dialkoxypolysiloxane isbelieved to interact with the thickener system as well as thepolyether/polysiloxane copolymer. These compounds have the followingstructures:

[0124] Dialkoxy Dimethicones

R—O—Si(CH₃)₂—O[Si(CH₃)₂—O]_(z)-Si(CH₃)₂—OR

[0125] where R is a straight chain alkyl group of 14-50, preferably16-24 carbon atoms, and

[0126] z=5-300

[0127] Polyether/Polysiloxane Copolymers (Dimethicone Copolyols):

(CH₃)₃—Si—O—[Si(CH₃)R₁₁—O]_(x)[Si(CH₃)R₈—O]_(y)—Si(CH₃)₃

[0128] where

[0129] x+y=5-400, preferably 15-200, and

[0130] R₈ is a polyether substituted alkyl group with the structure:

—R₉—O(C₂H₄O)_(p)(C₃H₆O)_(q)R₁₀;

[0131] where

[0132] R₉ is an alkyl group of 1 to 6 carbon atoms;

[0133] R₁₀ is hydrogen or an alky group of 1-22 carbon atoms;

[0134] R₁₁ is an alkyl group of 1 to 22 carbon atoms or phenyl;

[0135] p=2-300, preferably 8-100; and

[0136] q=0-100.

[0137] Note that branched chain polysiloxanes modified as shown in thetwo structures above are also possible.

[0138] The following are nonlimiting examples of emulsifier/emollientcomponents which improve thickening/stability of compositions of thepresent invention.

[0139] a. Certain wax emulsifiers/emollients have been found to beparticularly useful and include solid waxy esters such as: MyristylMyristate, Cetyl Palmitate, Myristyl Stearate, Stearyl Behenate, BehenylIsostearate, Isostearyl Behenate, Behenyl Behenate, Lauryl Behenate,Behenyl Erucate. These have the following formula:

R₁—CO₂—R₂

[0140] where:

[0141] R₁ is at least 14 carbon atoms; and

[0142] R₂ is an alkyl or alkenyl of at least 4 carbon atoms.

[0143] b. Long chain hydrocarbon di-esters, tri-esters, of polyhydricalcohols with melting point greater than 23° C. include solid esterssuch as glycerol tribehenate and sorbitan tristearate.

[0144] c. Pure lanolins and lanolin derivatives (e.g. hydrogenatedlanolin) provide excellent emolliency but can also improve the stabilityof the emulsion when used in combination with oil emollients.

[0145] d. Petrolatums provide excellent emolliency and can also improvethe stability of the emulsion when used in combination with oilemollients. Petrolatums are mixtures of oily and waxy long chainhydrocarbons.

[0146] e. Microcrystalline waxes and branched hydrocarbon waxes with amelting point greater than 50° C. and a molecular weight greater than400. An example of this includes but is not limited to Vybar 103 whichis a branched hydrocarbon with a number average molecular weight of 2800and is available from Petrolite Corp. of Tulsa, Okla. and “ULTRAFLEX”which is a microcrystalline wax also available from Petrolite Corp.

[0147] f. Oxidized waxes and modified hydrocarbon waxes may findapplication in the present invention. These are prepared from waxesmodified by oxidation, salts of oxidized waxes, maleic anhydride adductsof polyolefins and urethane derivatives of oxidized synthetic orpetroleum waxes. Applicable waxes could include Petrolite's Cardis orPetronauba microcrystalline and polyethylene-based oxidized products,Polymekon (salts) and Ceramer (anhydride adducts).

[0148] g. Fully saturated homopolymers of polyethylene or copolymers ofvarious alkene monomers may be used to form polymers with a molecularweight at or below 3,000 with a melting point below 130° C. and low meltviscosities. Applicable waxes could include “POLYWAX” available fromPetrolite Corp.

[0149] Fragrances

[0150] The formulations may also comprise a fragrance. If fragrances areincluded the fragrances must be chosen carefully since some fragrancesare known to cause skin irritation and/or sensitization reactions.

[0151] Antimicrobials

[0152] In addition to the lower alcohols present in the composition ofthe present invention, other antimicrobials may be added to enhance theantimicrobial action of the compositions of the present invention. Thismay be particularly desirable in critical uses such as presurgical handscrubs or presurgical patient skin scrub replacements. Suitableadditional antimicrobials include iodine and its complexed forms such aspovidone/iodine, chlorhexidine salts such as chlorhexidine digluconate(CHG), parachlorometaxylenol (PCMX), hexachlorophene, phenols,surfactants comprising a long chain hydrophobe (C12-C22) and aquaternary group, triclosan, Lauricidin, quaternary silanes, hydrogenperoxide, silver, silver salts such as silver chloride, silver oxide andsilver sulfadiazine and the like. In order to reduce chances forirritation and yet maintain efficacy, the antimicrobial level should beadjusted to the minimum level which maintains a low bacteriologicalcount for 6 and most preferably for 12 hours after application.

[0153] The most preferred additional antimicrobial is chlorhexidinesince it is capable of ensuring long term antimicrobial efficacy. Ifchlorhexidine is added to the present invention it is preferably presentas a soluble salt. The diacetate and digluconate salts are preferred.The most preferred antimicrobial is chlorhexidine digluconate (CHG). CHGis preferably present at a concentration of 0.05-5.0%, more preferablyfrom 0.1-3% and most preferably from 0.25-2% by weight. Chlorhexidine isa bis(diguanide) and therefore is very basic and is capable of formingmultiple ionic bonds with anionic materials. For this reason,chlorhexidine-containing thickener system are preferably based onnon-ionic and/or cationic emulsifiers. Certain zwitterionic, veryinsoluble, or non-precipitating anionic emulsifiers may also be useful.

[0154] Foams

[0155] The compositions of the present invention may also be formulatedinto an aerosol foam or mousse by addition of an appropriate propellant.The propellant must be chosen to ensure proper delivery from thecontainer to prevent clogging of the valve. The propellant can be chosenfrom chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs),hydrofluorocarbons (HFCs), perfluorinated alkanes, and lower alkanes(C1-C5) as well as nitrous oxide dimethyl ether and othersolvent-soluble propellants. Preferred propellants are lower alkanessuch as propane, butane, and isobutane since these result in a dramaticloss in viscosity making the formulation easy to dispense. A 70/30mixture of propane/isobutane is a particularly preferred embodiment. Inorder to produce an aerosol composition the antimicrobial lotion isfirst formulated and charged into an appropriate pressure ratedcontainer. If convenient, the formulation may be heated above the melttemperature in order to facilitate filling. The propellant is then addedunder pressure at approximately 2-30% preferably 3-20% by volume. Thepropellant may form a separate layer or may remain emulsified in thecomposition.

[0156] Alternate Applications for Hydro-Alcoholic Liquid CrystallineSolutions:

[0157] The compositions of this invention may be compounded with UVabsorbers and oils to deliver fast-drying sunscreens. Antimicrobialssuch as benzoyl peroxide may also be added to the formulations and theformulations may be useful as an acne medication. The systems of thisinvention may also be formulated with barrier compounds to form barriercreams and lotions. Materials which may be added to provide barrierprotection for use as skin barriers to protect against diaper rashinclude but are not limited to 0.1 to 60% aldioxa, allantoin, aluminumacetate, aluminum hydroxide, bismuth subnitrate, boric acid, calamine,cellulose (microporous), cholecalciferol, cocoa butter, cod liver oil(in combination), colloidal oatmeal, cysteine hydrochloride,dexpanthenol, dimethicone, glycerin kaolin, lanolin (in combination),live yeast cell derivative, mineral oil, peruvian balsam, peruvianbalsam oil, petrolatum, protein hydrolysate (1-leucine, 1-isoleucine,1-methionine, 1-phenylalanine, and 1-tyrosine), racemethionine, sharkliver oil, sodium bicarbonate, sulfur, talc, tannic acid, topicalstarch, vitamin A, white petrolatum, zinc acetate, zinc carbonate andzinc oxide. Formulations are also contemplated containing antifungalagents for treating fungal infections of the skin such as athlete's footand the like.

[0158] A related patent application entitled, “Stable HydroalcoholicCompositions,” attorney docket number 51800 USA 7A, Ser. No. 08/493,695,filed on Jun. 22, 1995 by inventors Asmus, Scholz and Charpentier ishereby incorporated by reference.

[0159] Since many of the compositions of the present invention containantimicrobials, it is important that they be dispensed in an efficaciousand precise amount. The compositions of the present invention can bedispensed in a discreet, substantially uniform amount using thedispensers disclosed in Applicants' Assignee's Copending U.S. patentapplication Ser. No. 08/668,198, filed Jun. 21, 1996, entitled“Dispenser for Antimicrobial Liquids,” issued as U.S. Pat. No.5,897,031, and Ser. No. 08/668,270, filed Jun. 21, 1996, entitled “DripResistant Nozzle for a Dispenser,” issued as U.S. Pat. No. 5,799,841.

Methods of Preparation

[0160] The compositions of the present invention may be prepared by avariety of techniques. For example, the process can often be as simpleas adding the thickener system to the hydroalcoholic solvent at atemperature above the melting point of the emulsifiers, mixing brieflyand cooling. Nevertheless, to ensure a composition of maximum stabilitythe components are preferably subjected to high shear (e.g. homogenized)for a limited time period while above the melting point of the thickenersystem followed by low shear mixing while cooling. The system should bemixed under high shear long enough to ensure a very small “droplet”size, however, excessive high shear mixing may result in decreasedviscosity and stability.

[0161] The cooling rate may be important depending on the particularthickener system. Certain thickener systems can be homogenized and thenallowed to cool slowly, however, rapid cooling appears beneficial formost systems.

[0162] The order of adding the components may also affect the stabilityand viscosity of the system. In general it works well to melt the mixedemulsifiers with aqueous-insoluble emollients together in one vessel.The hydroalcoholic solvent and any aqueous miscible emollients are mixedin a second vessel. Both components are heated above the meltingtemperature of the thickener system. The hot liquid components are mixedtogether rapidly followed by approximately 1 to 5 minutes ofhomogenization for typical batches under 500 grams. While still low inviscosity the system is stirred using moderate agitation and cooled. Itis also possible to add the molten thickener system along with anysolvent insoluble emollients to hot water (i.e., water at a temperatureabove the melting temperature) followed by high shear mixing andsubsequent dilution with alcohol. The processing variables includingamount and intensity of high shear mixing, rate of cooling, and order ofaddition are easily determined by one skilled in the art.

Test Methods

[0163] Viscosity

[0164] In the following Examples (except where indicated) viscosity wasmeasured at 23° C. at ambient pressure using a Brookfield LVDV-I⁺viscometer equipped with a model D Brookfield heliopath and T spindlesB-F. The spindle and speed was chosen for each particular sample suchthat the viscometer was operating in the middle of its range. Allsamples were allowed to equilibrate at 23° C. for 24 hours prior tomeasurement. Preferably the viscosity is taken at the lowest speedpossible while staying within 20-80% of the viscometer range and morepreferably between 30-70% of the range. In all cases the sample size andcontainer geometry was chosen to ensure that there were no wall effects.By “wall effects” it is meant the viscosity value is not affected by thecontainer and is essentially equivalent to the viscosity taken in aninfinitely large container. For this reason lower viscosity samplesrequired a larger sample size to accommodate the larger spindles. Thefollowing table outlines preferred spindles for various sampleviscosities. Sample Viscosity T Spindle to Use 1,000-100,000 B10,000-200,000 C 50,000-500,000 D 100,000-1,250,000 E 500,000-3,000,000F

[0165] The viscosity of each sample was taken as the highest relativelystable reading achieved on the first path the spindle traversed usingthe heliopath adapter.

[0166] Stability

[0167] The stability of samples was measured 24 hours after conditioningat ambient conditions by placing 12 ml of a formulation that formed alotion/cream in a 15 ml graduated centrifuge tube. The tube was thencentrifuged in a Labofuge B (Heraeus Sepatech GmbH, Model 2650, rotor2150 and buckets #2101) at 3000 rpm (2275× g when measured at thelongitudinal midpoint of the sample tube) for 30 minutes at 23° C.Stability is recorded as a volume percent separation in the Examplesbelow.

[0168] Melt Temperature (Tm)

[0169] The melt temperature was measured by placing approximately 15grams sample in a 25 cc sealed glass vial and placing the vial in awater bath. The temperature of the bath was increased periodically indiscrete increments and the contents checked after approximately 1 hourat a given temperature. The melt temperature was taken as thetemperature at which the mixture became very low in viscosity.

[0170] Minimum Inhibitory Concentration (MIC)

[0171] An overnight culture of E. coli ATCC₈₇₃₉ (lab strain 223) and/orS. Aureus ATCC 14154 (lab strain 502) grown on trypticase soy agarplates was resuspended in Mueller-Hinton Broth to a cell density of0.6-1.2×10⁶ colony forming units per milliliter. Chlorhexidine sampleswere prepared by adjusting CHG to 512 μg/ml in Mueller-Hinton Broth andserially diluting in two-fold steps in Mueller-Hinton Broth. TheCHG-containing Mueller-Hinton Broth was placed in 96-well sterilemicroliter plates and each well was inoculated with the bacteria. Theplates were then incubated for 24-48 hrs at 37° C. Bacterial growth wasdetermined visually by comparing the plates. The MIC was determined asthe lowest concentration of CHG that resulted in complete kill of thetest organism.

[0172] Cosmetic Properties/Tactile Testing

[0173] For use in presurgical disinfection the compositions of thisinvention are preferably formulated with emollients to achieve amoisturized but relatively dry feel. Lotions with excessive emollientstend to be perceived as greasy and can result in excessive clumping ofthe powder under surgical gloves. The formulations of this invention donot provide a tacky or sticky feel even in high humidity environmentsthroughout the application process. The invention formulationspreferably yield a smooth, soft, non-tacky, and moisturized feeling.Testing of the cosmetic or tactile properties of the compositions wasconducted with preferably greater than ten evaluators who applied apremeasured amount of product, approximately 2 ml. Since hand washingcan affect the feel of the compositions, evaluators washed thoroughlywith Ivory Skin Cleansing Liquid Gel hand soap available from Procterand Gamble, Cincinnati, Ohio before applying the sample. After drying,the composition was rubbed uniformly over the surfaces of both handsuntil the composition was dry. The feel of the composition on the skinduring subsequent washing with soap and water was also important.Approximately 30-60 min. after application of the composition the feelduring subsequent washing was evaluated. Preferred formulations did notresult in an abnormal feeling such as slimy, slippery, or stickycharacteristics.

EXAMPLES

[0174] The following Examples are provided to illustrate the inventionand are not intended to limit the scope of the invention.

Example 1 Alkyl Polyglucoside Thickener Systems

[0175] An alkyl polyglucoside emulsifier having an alkyl chain of 16 to18 carbons was obtained as Montanov 68 from Seppic Inc. of Fairfield,N.J. This highly crystalline emulsifier was combined with otheremulsifiers to form thickener systems in a hydroalcoholic solvent. Thesolvent was either 60:40 or 68:32 ethanol:water by weight. 200 proofethanol and distilled water were used. The Montanov 68/co-emulsifierratio was varied keeping the total emulsifier concentration fixed at 5%by weight according to the following table: Formulation (grams)Emulsifier A B C D Montanov 68 2 1.5 1 0.5 Co-emulsifier 0.5 1.0 1.5 2.060:40 ethanol:water 47.5 47.5 47.5 47.5

[0176] Each co-emulsifier/Montanov 68 composition was prepared using thefollowing procedure:

[0177] 1. The emulsifiers were heated above their melting temperature to75° C.

[0178] 2. The hydroalcoholic solvent was heated to 75° C. in a sealedjar.

[0179] 3. The hot hydroalcoholic solvent was rapidly added to the moltenemulsifiers.

[0180] 4. The mixture was homogenized at maximum speed for 4 minutesusing a Silverson L4R homogenizer available from Silverson Machines,Waterside England.

[0181] 5. The vessel was then immersed in 15-20° C. water with moderateagitation using an overhead paddle impeller for 20 minutes. FormulationViscosity (cps) and/or % Separation by Volume Emulsifier Solvent A B C DNikkol BB-5 (beheneth-5) 60:40 240,000 cps 2200 cps 29300 cps 26600 0%separation 0% 0% 0% Nikkol BB-5 (beheneth-5) 68:32  1500  48000 5700025000 Nikkol BB-10 (beheneth-10) 68:32  3400  17000  9300 NS NikkolBB-10 (beheneth-20) 68:32  32000  6800  450 NS Brij 52 (ceteth-2) 60:40  950 240000 36000 43000 Brij 58 (ceteth-20) 60:40  56000  60000  770 <100 Brij 72 (steareth-2) 60:40 470000  66000 48000 49000 Brij 72(steareth-2) 68:32 NS*  1500 34000 14000 Brij 76 (steareth-10) 68:32 35000  14600  3100  <100 Brij 78 (steareth-20) 60:40 294000  54000 6200  270 Brij 78 (steareth-20) 68:32  2700  1300  200 NS Unithox420(C3 1 alkyl-2EO) 68:32   730   850  600 NS Unithox 450(C3 1alkyl-9.8O) 68:32   600   770 77600 NS Incromine BB 60:40 NS  3600 70000630 (behenmidopropyldimethyl 0% <2% 24% amine) Incromine BB 68:32  6000  420  520 NS Incromine BB gluconate 60:40   75  23000  1200  2000 50%0% 0% 5% Armid 18 (octadecenamine) 60:40  <100 NS NS NS Lanette 18(Stearyl alcohol) 60:40 NS NS NS NS Uniwax 1750 (stearamide) 60:40 NS NSNS NS Triton X-15 68:32 NS NS NS NS (octylphenol ethoxylate) Triton X-3568:32 NS NS NS NS (octylphenol ethoxylate)

[0182] The results show that certain thickener systems form stableviscous compositions. Those thickener systems that form stablecompositions have widely varying viscosities depending on theemulsifiers and the ratio of the alkylpolyglucoside to co-emulsifier.For example, mixtures of Montanov 68 and Brij 52 had viscosities whichvaried from 950 to 240,000 cps. This example also illustrates the effectalcohol:water ratio has on resulting stability and viscosity. Forexample, at an ethanol:water ratio of 60:40, the Montanov 68:Brij 72system had a maximum viscosity of 470,000 cps at a weight ratio of 4:1(formulation A). When the ethanol:water ratio was increased to 68:32 the4:1 ratio was no longer stable and the maximum viscosity was only 34,000cps at a weight ratio of 2:3 (formulation C). Similar shifts appear forthe Montanov 68:Nikkol BB5 and Montanov 68:Brij 78. It appears thathigher viscosities are achievable at lower alcohol levels presumably dueto lower solubility of the emulsifiers and that peak viscosities appearat higher concentrations of Montanov 68 presumably due to the highlycrystalline nature of alkyl polyglucoside emulsifiers.

[0183] The results also indicate that the size of the hydrophilic groupinfluences the stability and viscosity even within the group of mixedemulsifiers which produce stable systems. For example, as the degree ofethoxylation increases, the hydrophilic group size increases and, ingeneral, the peak viscosity decreases. For example, within the cetethseries (Brij 52-58) the maximum viscosity is 240,000 cps for Ceteth-2whereas Ceteth-20 had only a maximum viscosity of 60,000 cps. Similarresults were found for the steareth series (Brij 72-78) and the behenethseries (Nikkol BB series).

Example 2 Alkyl Polyglucoside/Brij 72 Optimization

[0184] A series of 15 formulations were prepared using a three componentmixture design based on the results of Example 1. The followingconcentration ranges were investigated using a solvent ratio of 68:32ethanol:water. Component Percent by weight Montanov 68 0.26-3 Brij 721.0-5.2 Solvent 94-98

[0185] Each formulation was prepared and subsequently tested forstability and viscosity. The viscosities of the resulting formulationsranged from less than 50 cps to 93,600 cps. Stability results rangedfrom 0-83%. Examples of several optimized formulations appear below:Stability Montanov Viscosity (% volume Formula 68 Brij 72 Solvent (cps)separation) Percent by weight A 0.26 5.20 94.54 65,000 3 B 3.00 3.00 9493,600 0 C 2.20 2.92 94.88 72,000 0 D 2.20 1.92 95.88 30,000 0 E 1.802.70 95.5 30,000 0 F 3.20 2.30 94.5 50,000 0

[0186] These results together with those of Example 1 indicate that theviscosity of the formula for this thickener system is dependent upon theratio of the emulsifiers. The results also indicate that even whenvarying the ratio of the emulsifiers in thickener systems, highviscosities are still obtained while maintaining acceptable stabilityvalues. Furthermore, the total concentration of thickener systemnecessary to achieve a certain viscosity varies considerably dependingon the ratio of emulsifiers. For example, Formula D had a viscosity of30,000 cps with a total emulsifier concentration of only 4.12% byweight.

Example 3 Alkylpolyglucoside Ternary Thickener Systems

[0187] Based on the results obtained in Example 2, formulae E and F werechosen for use as base systems to which a third emulsifier was added tofurther increase the viscosity. The third emulsifier was added atconcentrations of 0.3, 0.8, 1.3 and 1.8% by weight keeping the ratio ofMontanov 68 and Brij 72 at the ratios found effective in formulations Eand F of Example 2 according to the following table: Formula Component AB C D E F G H Amount (grams) Montanov 68 0.92 0.92 0.92 0.92 1.11 1.111.11 1.11 Brij 72 1.37 1.37 1.37 1.37 1.55 1.55 1.55 1.55 Coemulsifier0.15 0.40 0.65 0.90 0.15 0.40 0.65 0.90 Solvent 47.57 47.32 47.07 46.8247.19 46.94 46.69 46.44

[0188] The solvent used was 68:32 ethanol:water. The formulations wereprepared and subsequently tested for stability and viscosity. The thirdco-emulsifiers used were behenyl alcohol (Lanette 22, Henkel Corp.) andstearamide diethanolamine (Lipamide S, Lipo Chemical of Paterson, N.J.).The following viscosity results were found: VISCOSITY (cps) CoemulsifierA B C D E F G H Lipamide S 42,500 70,500 82,800 111,000 75,500 120,00091,100 90,000 Lanette 22 59,100 88,800 93,600  92,300 14,500  62,00086,800 81,600

[0189] All formulations had stability values of 0% separation exceptformula A/Lanette 22 which showed a trace (<5%) amount of separation.The results indicate that addition of a third emulsifier into thethickener system can increase the viscosity. The results also indicatethat the length of the hydrocarbon on the third emulsifier does notnecessarily predict viscosity. In this example, Lipamide S, although ithas a significantly shorter hydrocarbon chain than Lanette 22,generally, produced higher viscosity compositions.

Example 4 Effect of Shear on Viscosity and Stability

[0190] Formulation C from Example 2 was used as a base system to testthe effect of varying levels of shear on the resulting viscosity andstability of the compositions. The thickener and the solvent were heatedto 75° C. in separate containers. The solvent was added to theemulsifiers rapidly and the composition mixed as described below: A handshaken for less than 1 minute B hand shaken for less than 1 minute,sealed and placed on a roller for 4 hours at 50 rpm C stirred 20 minutesat low speed with an overhead stirrer D homogenized for 4 minutes,sealed and allowed to sit E homogenized for 2 minutes, stirred 10minutes at low speed with an overhead stirrer F homogenized for 1minute, stirred 10 minutes at low speed with an overhead stirrer Ghomogenized for 4 minutes, stirred 20 minutes at low speed with anoverhead stirrer H homogenized for 4 minutes, placed on a roller for3.25 hours at 50 rpm I homogenized for 4 minutes, placed on a roller for50 minutes at 50 rpm

[0191] A wide variety of consistencies resulted as indicated below:Viscosity Stability Formula Appearance (cps) (% separation) A white,pearlescent, crystalline 7,400 64 regions B opaque white cream 1,290 0 Copaque, pearlescent, cohesive 60,700 0 D bluish, transparent, 27,600 0pearlescent, cohesive E opaque, pearlescent, cohesive 81,200 0 F opaque,pearlescent, cohesive 85,500 0 G white, opaque, pearlescent, 61,700 0cohesive H bluish opaque, not cohesive 995 0 I * 27,000 0

[0192] The results indicate that for this thickener system the intensityand degree of mixing have an affect on the resultant product. Both toolittle mixing (Formula A) and too much mixing (Formula H) haddeleterious affects on the viscosity. A preferred method of mixing is acombination of brief (1-2 minutes) high shear homogenization followed byoverhead stirring for 10 minutes (Formulae E and F).

Example 5 Effect of Added Polymers

[0193] This example investigated the effects of adding various polymers((1) polymers containing pendant alkyl groups and (2) linear and solublein the solvent and (3) crosslinked and swellable in the solvent) to athickener system. The polymers used were:

[0194] (1) Crodacel QS (Croda, Inc. of Parsippany, N.J.)—Stearyldimoniumhydroxypropyloxyethyl cellulose

[0195] (2) Quatrisoft LM-200 (Amerchol Corp. Edison, N.J.)Lauryldimmonium modified hydroxyethylcellulose (CTFA Polyquatemium 24)

[0196] (3) Salcare 96 (Allied Colloids of Sufolk, N.J.),polymethacryloyloxyethyl trimethylammonium chloride (CTFA Polyquaternium37)

[0197] The polymers were added to the formulations at levels of 0.1,0.25, 0.37, 0.5 and 0.75% by weight according to the following table:Formula Component 0.1 0.25 0.37 0.50 0.75 Formula Number Amount (grams)Montanov 68 2.0 2.0 2.0 2.0 2.0 Brij 76 0.5 0.5 0.5 0.5 0.5 Polymer 0.050.125 0.185 0.25 0.37 Solvent 47.45 47.37 47.32 47.25 47.12 68:32

[0198] The formulations were prepared as in Example 1 except thepolymers were added to the solvent (68:32 ethanol:water by weight) priorto mixing. Note that formula number refers to weight percent polymer. Ifthe polymer was supplied in water, the water in the solvent system wascorrected to reflect the exact formulation shown above. The results areshown below: Viscosity (cps) Polymer Polymer added added Post high shearConcentration Before high 48 Polymer (weight %) shear Initial time hoursNone 0 3700 3700 Crodacel QS (1) 0.1 <500 — — 0.25 22000 — — 0.50 292000178000 231000 0.75 152000 42500 93000 Quatrisoft 0.1 <500 — — LM-200 (2)0.25 62000 32900 14700 0.37 31000 — — 0.50 <500 — — Salcare (3) 0.1 1550— — 0.25 1500 — — 0.37 155000 — — 0.50 296000 — —

[0199] The results indicate that Crodacel QS with pendant stearyl groupshas a synergistic effect on the viscosity of the composition. This isevident since the polymer itself contributes little thickening. CrodacelQS is supplied as a 20% aqueous solution and at concentrations under 1%by weight the viscosity of this polymer in 68:32 ethanol:water is lessthan 50 cps. It is believed that this polymer associates with thethickener system in the formulation. The Quatrisoft polymer alsocontributed to thickening the formulations. The Crodacel QS andQuatrisoft polymer formulations with the peak viscosity were preparedagain except that the polymer was added to the thickener system afterthe composition was prepared and cooled to room temperature. Even underthese conditions the polymer containing formulation had a higherviscosity than the formulation without the polymer. A preferred methodof preparing the formulations is adding the polymer to the hot solventbefore adding the thickener system so that the polymer and emulsifierscan interact while above the melt temperature. The Crodacel formulationswere also found to be stable, showing no separation.

Example 6 Effect of Added Emollients

[0200] A series of wax, oil occlusive emollients and humectant typeemollients were added to a thickener system to evaluate the effect onviscosity. Each emollient was added to two formulations shown below:Formula A B Component Amount (grams) Montanov 68 4 1.8 Brij 76 2 0.45Croadcel QS (20% solution in water) 0 1.13 Ethanol:water 68:32 by weight90.3 40 Emollient 3.7 1.7

[0201] The procedure of Example 1 was used to prepare the formulationsexcept emollients were either added to the hot solvent or the thickenersystem prior to mixing. Glycerine and Quamectant were added to thesolvent. Other emollients were added to the thickener system. Theviscosity results are shown below: Viscosity(cps) Emollient NameChemical Description A B Bernel octyldodecyl myristate 12,900 39,000Ester 2014¹ Bernel trioctyldodecyl citrate 15,600 168,000 Citmol 320¹Lipovol tridecyl stearate and 28,000 39,000 MOS 130²tridecyltrimellitate and dipentaerythritol hexacaprate Fitoderm³Squalane 39,200 93,750 DC344⁴ cyclomethicone <100 2,700 Jarcol I-16⁵2-hexyldecanol <50* 59,100(0.5 wt %) 2,900 (1 wt %) Lexol PG 865⁶propyleneglycol <50 dicaprylate/dicaprate Glycerin glycerol 28,600274,000 Quamectant 6-(N-acetyl- 61,000 141,000 AM50⁷ amino)-4-oxahexyl-trimethylammonium chloride Astorwax OK paraffin wax 39,000 236⁸

[0202] This example shows that some emollients affect final viscosity ofthe composition. Humectants which are soluble in the system appear tohave much less effect, such as glycerin. The greatest viscosityreduction appears due to adding emollients with branched chainhydrocarbons (e.g., Jarcol I-16).

Example 7 Effect of Addition of Borate Ion

[0203] In this example sodium borate was added to a premadealkylpolyglucoside thickener composition. It is believed that the borateion associates with adjacent polyglucose hydrophilic head groups to holdthem in the “micelle” structure thus elevating the melt temperature.

[0204] A solution of sodium borate in water was added to a concentrationof 0.7% by weight to the formulation of Example 6A containing Fitodermsqualane. The resulting formulation with sodium borate was visiblythicker with a higher melt temperature. The sample without borate meltedrapidly when dispensed into the palm of a hand. The sample with boratedid not melt when dispensed into the hand.

[0205] To evaluate the effect of borate ion at different pH values,10.21 grams boric acid was added to 160 grams distilled water. Using apH meter sodium borate was added while stirring until a pH of 5 wasreached (0.33 grams sodium borate). A 57 gram sample was removed. To theremaining solution was added sodium borate to a pH of 6.0 (1.6 gramssodium borate). Again, a 57 gram sample was removed and to the remainingsolution was added 1.94 grams sodium borate to reach a pH of 7.0. Thesethree solutions were added to the following formulation: ComponentConcentration (weight percent) Montanov 68 4 Brij 76 1 Crodacel QS (20%solution in water) 2.5 Ethanol/water 68:32 92.5

[0206] The base formulation was prepared according to Example 1 with theCrodacel QS added to the solvent system prior to mixing. The boratesolutions were added to yield the weight percent borate shown in thetable below after the thickener system had cooled to room temperature.The following observations and melt temperatures were recorded: Boratewt % Soln pH Boron Consistency Tm (° C.) None- 0 Stable <31 CONTROL 50.02 stable and thicker than control   31 5 0.04 thicker than pH 5 with0.02% Borate   34 5 0.08 thicker than pH 5 with 0.04 Borate   35.5 50.12 similar to pH 5 with 0.08 Borate >35.5, <39 6 0.02 syneresis, notas thick as pH 5 analog <31 6 0.04 syneresis, not as thick as pH 5analog   31-34 6 0.08 syneresis, not as thick as pH 5 analog   31-34 60.11 syneresis, not as thick as pH 5 analog   35.5 7 0.014 more phaseseparation than pH 6 <31 analog, no thickening 7 0.04 more phaseseparation than pH 6 <31 analog, no thickening 7 0.07 more phaseseparation than pH 6   31 analog, no thickening 7 0.10 more phaseseparation than pH 6   31 analog, no thickening

[0207] The results show that adding borate ion to the compositionincreases the melt temperature. This is more pronounced at lower pHvalues.

Example 8 Effect of Ethanol Concentration on Melt Temperature

[0208] Formulations containing 7% Montanov 68, 1.76% Brij 76, 0.5%Crodacel QS polymer (on a solids basis)were prepared in accordance withExample 5. For each formulation the percent solvent was held constant at90.74% but the ratio of ethanol:water was varied from 50:50 to 68:32.The melt temperature was measured as described above. Solvent ratio MeltTemp Ethanol:water (° C.) 50:50 40 55:45 38.5 60:40 36 64:36 36 68:32 33

[0209] The results illustrate that as the alcohol:water ratio isincreased, the melt temperature decreases for this thickener system.

Example 9 Antimicrobial Efficacy of Compositions ContainingChlorhexidine Gluconate

[0210] The following thickener systems were produced with and withoutchlorhexidine gluconate (CHG) to determine if the CHG is effectivelydelivered in a thickener system. The borate pH 5 solution from Example 7was used. Formula Amount (grams) Component 1 2 3 4 5 6 7 8 9 10 Montanov68 2.0 0.77 2 0.76 2 0.76 2.0 0.69 Brij 76 0.5 0.19 0.5 0.19 0.5 0.190.5 0.17 Crodacel QS (20%) 1.25 0.48 1.25 0.48 1.25 0.43 Kenamide B 0.250.10 (behenamide, Witco) Borate ion solution, pH 5 5.61 1.93 CHG (20%soln) 0.25 0.48 0.48 0.48 Ethanol:water 68:32 47.5 18.2 46.25 17.6 4617.5 46.25 15.9 Ethanol 6.8 6.77 Water 3.2 2.98

[0211] Minimum Inhibitory Concentration (MIC) for both E. Coli and S.Aureus was determined according to the test methods outlined above andis reported in the table below: MIC (μg/ml) Sample E. coli S. aureus1 >256 >256 μg/ml 2 4-8 4 3 >256 >256 4 2-4 2 5 >256 >256 6 4 47 >256 >256 8 4 4 9 >256 >256 10  4-8 4 0.5% CHG std. 4 4 Hibiclens* 4 4

[0212] The results show that none of the components of this formulationof the invention inactivate the CHG.

Example 11 A Presurgical Antimicrobial Hand Lotion Using anAlkylpolyglucoside Containing Thickener System

[0213] The following formulation was prepared using the procedure ofExample 6: Component Wt. % Montanov 68 4.0 Brij 76 1.0 Kenamide B 0.5Lipovol MOS 130 1.5 Fitoderm 2.3 350ctk polydimethyl siloxane (CarbideL45/350) 0.50 Crodacel QS (20% solution in water) 2.5 NaCl (2% inwater)* 2.5 Ethanol 59.3 Water 25.9

[0214] The resulting formulation had an ethanol:water ratio of 68:32.This formulation was applied to hands repeatedly throughout the day byseveral volunteers. Hands were washed with Ivory soap betweenapplications. The feel of the lotion was well received and skincondition was maintained.

Example 12 Alkylpolyglucoside/Polyethoxylated Alkyl Alcohol/Ester ofShort Chain Alcohol/Amine Oxide/Quaternary Amine Thickener Systems

[0215] The following compositions were prepared by heating separatelythe solvent (alcohol and water) and the thickener system to 70° C. Thesolvent was rapidly added to the thickener system and homogenized on aSilverson L4R homogenizer. This was followed by 10 minutes of stirringwith an overhead inverted “T” paddle stirrer with the glass containerimmersed in a 10-15° C. water bath. Compositions A-C were mixed for 10minutes while C and D were mixed for 4 and 5 minutes respectively. Thecompositions were then cooled to allow the emulsifiers to solidify.Component A B C D E F G Amount (grams) Montanov 68 1.2 1.2 1.2 3.2 3.21.80 1.80 Brij 76 0.3 0.3 0.3 0.8 0.8 0.45 0.45 Incromine oxide 0.5 0.751.0 B30P*(30% solution in water) Nikkol CA- 0.18 0.35 2580** IncroquatDMB- 0.50 0.50 90****(90% in 10% ethanol) Lanette 22 0.65 1.3 Kemester0.6 0.6 0.6 1.6 1.6 0.23 9022*** 68:32 27.40 27.15 26.90 73.57 72.5740.45 40.23 Ethanol/water

[0216] Compositions A, B, and C were viscous creams with littleelasticity. Visually, sample C was more viscous than B which was moreviscous than A. This shows that the amine oxide contributed to theviscosity of the compositions. Compositions D and E were very viscousand quite elastic in nature. Composition E was significantly thicker.This shows that this quaternary amine contributed to a more elasticcomposition. Samples F and G were opaque white creams of goodconsistency. Sample G was more viscous than Sample F. Sample F had somesyneresis.

[0217] The melting temperature (Tm) of the compositions was measuredaccording to the protocol outlined above. The results are shown below:Composition A B C D E F G Tm(° C.) 37-39 39 39 39 42 38 38 Heat cycle *HS HS HS HS HS HS HS

Example 13 Long Chain Alkylpolyglucoside/Polyethoxylated AlkylAlcohol/Quaternary Amine Thickener System

[0218] A series of 10 formulations were prepared using a three componentmixture design with the total emulsifier level fixed at 2% by weight.The following concentration ranges were investigated using a solventratio of 68:32 ethanol:water further containing 0.5% by weight CHG.Emulsifier Percent by weight Eassi 624MP 0.25-1.5% by weight Nikkol BB50.25-1.5 Incroquat DBM-90 0.25-1.5

[0219] Eassi 624MP is an alkylpolyglucoside prepared from an alcoholfeed stock of 92% by weight behenyl alcohol and was obtained from SeppicInc., Fairfield, N.J. The product had a melting point of 83° C. and a 5%aqueous solution had a pH of 6.4. Each formulation was prepared byadding 49 grams solvent at 80° C. to 2 grams thickener system at 80° C.followed by 45 seconds of homogenization followed by 3 minutes ofoverhead mixing while immersed in a 15° C. water bath. The samples weresubsequently diluted to 2% solids by adding 49 grams solvent mixture.Each composition was subsequently tested for viscosity and Tm. Theviscosities of the resulting formulations ranged from less than 165,000cps to 309,000 cps. Examples of several preferred formulations appearbelow: Sample Component A B C D E F Amount (grams) Eassi 624MP 1.5 1.080.25 0.66 0.25 0.87 Nikkol BB5 0.25 0.46 1.5 0.67 0.88 0.88 IncroquatDBM 0.25 0.46 0.25 0.66 0.87 0.25 90(90%) Viscosity (cps) 309,000192,000 175,000 227,000 252,000 220,000 Tm (° C.) >57° C.    52-57 5252-57    44 52-57

[0220] The results show that the behenylpolyglucoside increases the melttemperature. Comparing the melt temperatures of this example with thoseof Example 12F shows that increasing the chain length of the hydrophobesin the thickener system increases the Tm. The thickener system of theformulations in this example produce homogenous viscous creams withvarying ratios of the emulsifiers.

Example 14 Disinfectant Hand Lotion Based on AlkylpolyglucosidePolyethoxylated Alkyl Alcohol/Quaternary Amine Thickener System

[0221] Disinfectant hand creams/lotions were prepared based on thethickener system of Example 13F. The compositions are shown below:Component A B Amount (grams) Eassi 624MP 0.88 0.88 Nikkol BB5 0.87 0.87Incroquat DBM 90 (90% solution in ethanol) 0.25 0.25 Silwet 7001* (75%solution in water) 1.33 1.33 DC344¹ 2.00 2.00 Procetyl 50** 2.0 Macol30P’’’ 1.00 Arcol PPG-725*** 2.00 2.00 Bernel Ester 2014 2.00 PluronicP-65**** 0.50 68:32 ethanol:water 91 89

[0222] The compositions were prepared by heating the solvent and Silwetto 75° C. in one container and heating the remaining components to 75°C. in a second container. The solvent was rapidly added to theemulsifiers/emollients followed by 45 seconds of homogenization with nosubsequent mixing. Both formulae had a nice feel when 2 ml was appliedto the hands and rubbed in the skin. Formula B was a little moreappealing due to a better hand feel. Tm was measured as 48° C. for A and45.5° C. for B.

Example 15 Polyglycerol Ester Containing Thickener Systems

[0223] The formulations for Example 15 (as described in the table below)were prepared by heating the thickener system and the solvent inseparate jars to 75° C., rapidly adding the solvent to the thickeners,shaking vigorously, and stirring with an overhead stirrer for 10 minuteswhile immersed in a 10-15° C. water bath. The Tm was measured asdescribed above. Sample Component Chemical Description A B C Amount(grams) Decaglyn 1-S decaglycerolmonostearate, 1.35 Barnet of Paterson,NJ Hexaglyn 1-S hexaglycerolmonostearate, 1.35 Barnet of Paterson, NJTetraglyn 1-S tetraglycerolmonostearate, 1.35 Barnet of Paterson, NJBrij 76 Steareth-10 0.23 0.23 0.23 Ethanol:water 42.98 42.98 42.98 68:32Tm (° C.) 44 38.5 38.5

[0224] The samples were tested for stability. Samples A, B and Cproduced stable compositions of varying viscosity. Visual observationshowed that sample A had a higher viscosity than B which was higher thanC. A longer polyglycerol chain length is preferred in this thickenersystem and even though the longer chain polyglycerol emulsifier isexpected to be more soluble in the solvent system, it increased the Tmof the formulation.

Example 16 More Polyglycerol Ester Containing Thickener Systems

[0225] The following compositions were prepared as described in Example15. Sample Component A B Amount (grams) Decaglyn 1-S Polyaldo 10-1-S*1.5 1.5 Brij 76 0.5 0.5 Incroquat DBM90 0.56 0.38 Arcol PPG-425*** 2.0Procetyl 50 2.0 Ethanol/water 68:32 47.44 43.63 Tm (° C.) 39-41 40-44

[0226] Samples A and B were homogenous viscous translucent almostgel-like compositions. Sample B had a fairly nice feel but was a littletacky.

Example 17 Polyglycerol Ester/Amine Oxide/Quaternary Amine ThickenerSystems

[0227] The following compositions were prepared as described in Example15. The viscosity (Tm) was measured for each sample. Sample Component AB C D Amount (grams) Polyaldo 10-1-S 1.2 0.9 0.6 0.3 Incromine Oxide 1.02.0 3.0 4.0 B30P (30% solution in water) Incroquat 0.28 0.28 0.28 0.28DBM-90 (90% solution in ethanol) Ethanol:water 47.5 46.8 46.1 45.4 68:32Viscosity (cps) 530,000 105,000 146,000 75,000 Tm (° C.) 40 40 40 37

[0228] The samples were allowed to cool after melting. All samplesproduced translucent gel-like compositions of acceptable viscosity andmelt temperature. Samples C and D returned to a uniform appearance afterheating above the melt temperature and allowing to slowly cool.

Example 18 Decaglyceroltetrabehenate Containing Thickener System

[0229] The following compositions were prepared by heating the thickenersystem and solvent in separate jars to 80° C., rapidly adding thesolvent to the thickener, homogenizing for 20 seconds, and stirring withan overhead stirrer for 10 minutes while immersed in a 10-15° C. waterbath. The Tm and viscosity were measured for some of the samples. SampleComponent A B C D E F G H Amount (grams) Kemester 9022 0.8 0.60 0.400.20 Incromine Oxide 2.67 2.0 1.33 0.67 B30P (30% solution in water)Decaglyceroltetrabe 0.20 0.40 0.60 0.80 0.20 0.40 0.60 0.80 henateEthanol:water 68:32 48.72 48.72 48.72 48.72 46.86 47.32 47.79 48.26 Tm(° C.) 49 — — — — 39 39 — Viscosity (cps) 135,000 — — — 8,500 6,5006,700 10,500

[0230] Samples B-D produced homogenous compositions of low viscosity.Sample A was an opaque viscous cream with a fairly high melttemperature. Samples E-H were lower in viscosity and melt temperaturethan Sample A.

Example 19 Ester/Amine Oxide/Quaternary Amine Thickener Systems

[0231] The following compositions were prepared using the procedureoutlined in Example 15. Sample Component A B C D Amount (grams) Kemester9022 0.9 0.9 0.9 0.9 Incromine Oxide B30P 2.0 2.0 2.0 2.0 (30% solutionin water) Nikkol CA-2580 0.29 0.17 (85% solution in water) Incromine BBgluconate 0.68 1.37 (36.5% solution in water) Ethanol:water 68:32 46.8146.93 Ethanol 31.42 30.82 water 15.0 14.91 Tm (° C.) — — 49 —

[0232] Samples A and B did not produce stable homogenous compositions.Composition C and D produced viscous compositions but composition Dappeared non-uniform. The melt temperature of Composition C was quitehigh.

Example 20 Amine Oxide/Ester/Quaternary Amine Thickener System

[0233] A series of 18 formulations were prepared using a three componentmixture design. The total thickener level varied from 2.45 to 4.55% byweight. The following concentration ranges were investigated using asolvent ratio of 68:32 ethanol:water. Component Percent by weightIncromine Oxide B30P 0.80-1.87 Kemester 9022 1.40-2.47 Incroquat DBM-900.05-0.92

[0234] The compositions were prepared by heating the thickener systemand the solvent in separate jars to 75° C., rapidly adding the solventto the emulsifiers, shaking vigorously, and stirring with an overheadstirrer for 5 minutes while immersed in a 10-15° C. water bath. The melttemperature (Tm), viscosity and stability were measured as describedabove. All ratios produced stable compositions having a viscosity rangeof 10,000-270,000 cps and a Tm of 45-47° C. Elasticity was measured bygently stirring the sample and was judged on a scale of 1-5 where 5 wasa very stringy composition and 1 was viscous but not elastic. A few ofthe compositions prepared are shown below: Composition Component A B C DE Amount (grams) Kemester 9022 1.17 1.43 1.17 1.17 1.17 Incromine OxideB30P (30% 2.6 3.47 4.06 1.14 2.60 solution in water) Incroquat DBM90(90% solution in 0.60 0.33 0.30 0.33 0.05 ethanol) Ethanol:water 68:3260.63 59.45 59.45 62.36 61.18 Tm (° C.) 47 45 45 46 45 Viscosity (cps)280,000 270,000 270,000 250,000 30,000 Elasticity (1-5) 2 4.5 4 1 5

[0235] The results indicate that this thickener system produces stablecompositions with varying ratios of emulsifiers but that the physicalproperties of the compositions vary widely. Composition D is a preferredformulation since it is high in viscosity at low total solids content(2.83%), has very little elasticity and a high melt temperature.

[0236] The following disinfectant hand lotion was produced using thethickener system and the procedure of Example 14: Component Amount(grams) Kemester 9022 0.72 Incromine Oxide B30P 1.48 (30% solution inwater) Incroquat DBM90 0.10 (90% solution in ethanol) Pluronic P65 0.25Bernel Ester 2014 1.00 Macol CA30P 0.50 PPG725 1.00 DC344 1.10 Silwet7001 0.70 68:32 ethanol:water 43.28 

[0237] This composition was stable with a nice viscosity and a Tm of 41°C.

Example 21 Alkyl Alcohol/Quaternary Amine Thickener System

[0238] The following formulations were prepared using Lanette 22 (HenkelCorp of Ambler, Pa.), Behenyl Alcohol Nikkol CA-2580 (Barnet ProductsCorp., Paterson, N.J.), Behenyltrimethylammonium Chloride CompositionComponent A B C Amount (grams) Nikkol CA-2580 0.59 0.59 0.44 Lanette 221.5 2.00 1.63 68:32 Ethanol:water 47.91 47.41 47.93

[0239] The compositions were prepared by separately heating the solventand the thickener system to 65-70° C. The solvent was rapidly added tothe thickener system followed by stirring with an overhead paddlestirrer with the glass container immersed in a 10° C. water bath. Eachcomposition was mixed for 4.5 minutes after which the compositionscooled sufficiently for the emulsifiers to solidify.

[0240] All three compositions were viscoelastic. The samples appearedpearlescent with macroscopically obvious crystalline regions. Thecrystals appeared macroscopically lamellar in nature. A small amount ofsyneresis was seen on standing at 23° C. overnight. The Tm of sample Cwas approximately 47° C. (The sample did not melt uniformly and even at47° C. still had some solid regions.)

Example 22 Alkyl Alcohol/Ester/Quaternary Amine Thickener Systems

[0241] A series of 10 formulations were prepared using a three componentmixture design. The total thickener system level was held constant at2.00% by weight. The following concentration ranges were investigatedusing a solvent ratio of 68:32 ethanol:water containing 0.5% by weightCHG: Component Percent by weight Lanette 22 0.25-1.25 Kemester 90220.50-1.50 Incroquat DBM-90 0.25-1.25

[0242] The compositions were prepared by heating the thickener systemand the solvent in separate jars to 75° C., rapidly adding the solventto the thickener, homogenizing for 40 seconds on a Silverson L4Rhomogenizer at maximum speed, and stirring with an overhead stirrer for5 minutes while immersed in a 10-15° C. water bath. The Tm, viscosityand stability were measured. Only select ratios produced high viscositystable compositions having a viscosity range of 76,000-274,000 cps and aTm of 47-53° C. Stability was measured according to Example 1. Severalof the formulations are shown below: Sample Component A B C D E Percentby weight Kemester 1.50 0.50 1.00 0.50 0.67 9022 Lanette 22 0.25 0.250.75 1.25 0.92 Incroquat 0.25 1.25 0.25 0.25 0.42 DBM90 Ethanol: 98 9898 98 98 water 68:32 (0.5% CHG) Tm (° C.) 47 49 51 52 53 Viscosity 7600076000 250000 274000 125000 (cps) Stability (% <2 2 2 10 5 Volumeseparation)

[0243] The results indicate that this thickener system produces stablecompositions with varying ratios of emulsifiers but that the physicalproperties of the compositions differ considerably. Composition C is aparticularly preferred formulation since it has a high viscosity, highmelt temperature, and little separation. After standing for 1-2 days at23° C., all of the above formulae showed a small amount of syneresis,i.e. a small amount of clear low viscosity solvent phase separated onthe top of the sample.

Example 23 Addition of an Alkylene Alcohol

[0244] Oleyl alcohol was incorporated into the formulation shown inExample 22C by adding it to the molten thickeners prior to mixing withthe solvent. The composition is shown below: Component: Amount (grams)Lanette 22 0.38 Kemester 9022 0.50 Incroquat DBM90 0.14 Novol (oleylalcohol, Croda) 0.20 Ethanol:water 68:32 48.78 

[0245] A stable quite viscous gel-like composition resulted. The Tm wasmeasured as 50° C. The stability was measured as 5%.

Example 24 Addition of Dialkoxy Dimethicone and Polyether-PolysiloxaneCopolymers for Enhanced Stability

[0246] The compositions of Example 22 had very good viscosity, Tm, andstability properties but showed a slight amount of syneresis onstanding. Surprisingly, adding a combination of dialkoxy dimethicone andpolyether-polysiloxane copolymers ensured no syneresis and also provideda smooth non-waxy feel. The following system was prepared using thethickener ratios identified in Example 22C and the procedure of Example22. The Abil wax2440 was heated with the emulsifiers while the AbilB88183 was heated in the solvent: Base Systems Component Amount (grams)Kemester 9022 0.50 Lanette 22 0.38 Incroquat DBM90 (90% solution inethanol) 0.14 Abil wax2440¹ 0.25 Abil B88183² (35% solution in water)0.71 Ethanol:water 72:28 48.03 Tm (° C.) 47

[0247] The system was stable and showed no signs of syneresis even after13 days of room temperature storage. The melt temperature of the baseformulation is reduced compared to that of Example 22C most likely dueto the increase in the level of ethanol in the solvent.

[0248] This formulation was evaluated for activity of CHG at 0.5% byweight and was also used to prepare a hand lotion containing numerousemollients by preparing the following formulations: Sample Component 1 23 4 5 6 7 8 Amount (grams) Kemester 9022 1.00 0.52 1.00 0.50 1.00 0.51Lanette 22 0.75 0.39 0.75 0.38 0.75 0.38 Incroquat DBM90 0.28 0.15 0.280.14 0.28 0.14 (90% solution in ethanol) Abil 2440 0.75 0.38 0.75 0.38Abil 88183 (35% 1.43 0.72 1.43 0.72 solution in water) Pluronic P65 0.500.26 glycerin 1.00 0.51 Dermol DIPS¹ 1.00 0.51 Macol CA30P 1.00 0.51Arcol PPG 725 2.00 1.03 DC344 2.00 1.03 CHG soln (20% in 0.25 1.39 1.261.28 water) Ethanol:water 68:32 97.97 51.21 95.79 48.15 88.29 45.29Ethanol 6.8 6.77 Water 3.2 2.98 E. coli 223 MIC >256 4 >256 2-4 >2562-4 >256 4 (μg/ml) S aureus 502 MIC >256 4 >256 2 >256 4 >256 4 (μg/ml

[0249] A 0.5% CHG standard was also run and found to have an MIC of 4for both bacterial strains. These results indicate that the thickenersystem does not interfere with the CHG activity and that thecompositions have no inherent antimicrobial activity except due to theethanol:water solvent system. Sample 7 had nice cosmetic properties.

Example 25 Repeat Application of a Preferred Hand Lotion Composition

[0250] The following hand lotion composition was prepared as describedin Example 23. Component Weight % Kemester 9022 1.0 Lanette 22 0.75Incroquat DBM90 (90% solution in ethanol) 0.28 Abil 2440 0.75 Abil 88183(35% solution in water) 1.43 glycerin 2.50 Dermol DIPS 1.00 Dermol 489²1.00 Arcol PPG 725 2.00 DC344 0.50 Dermol G-7DI¹ 0.5 Ethanol:water 68:3288.29

[0251] The formulation was first evaluated in tactile testing byapplying 2 ml in the palm of one hand and rubbing the lotion thoroughlyinto both hands.

[0252] This composition had good cosmetic properties. A panel of fivevolunteers then applied the lotion as described eight times a day inapproximately 1 hour intervals after first washing with water and Ivoryliquid soap (Procter and Gamble, Cincinnati, Ohio) and drying the handsthoroughly before each application. This was repeated for a total of 5days and was conducted during the winter to exaggerate any potentialdrying effect. The lotion was rated positively in all cosmeticcategories surveyed including overall feel, lack of oiliness,moisturization, smoothness during application, and feel while washing.Expert grading was used to judge the condition of the skin. Using a 5point scale:

[0253] 1=Very slightly scaly—occasional scale not necessarily uniformlydistributed

[0254] 2=Slightly Scaly—Scale in sulci and on plateaus. More visiblescale that is more uniformly distributed

[0255] 3=Scaly—Visible scale giving the overall appearance of the skinsurface a whitish appearance. Definite uplifting of edges orscale-sections. Hand is rough to the touch.

[0256] 4=Scaly to very scaly—More scale and pronounced separation ofscale edges from skin, although they may still be lying flat on the skinsurface. Some evidence of cracking in sulci and on plateaus. Somereddening may appear.

[0257] 5=Very scaly—excessive cracking of skin surface. Skin appearsvery irritated with widespread reddening

[0258] The skin condition was evaluated initially and at the end of days3 and 5 and results are shown in the table below. Time Mean Skin Rating*Standard Deviation Initial 2.6  0.93 Day 3 1.80 1.53 Day 5 1.60 0.77

[0259] The results indicate that overall the skin conditionsignificantly improved.

Example 26 Polyethoxylated Alcohol/Ester/Quaternary Amine ThickenerSystem

[0260] The following thickener system compositions were prepared byheating the solvent and the thickener system separately to 75° C. Thesolvent was added to the thickener system and homogenized on a SilversonL4R at maximum speed for 45 seconds followed by stirring with anoverhead paddle stirrer in a glass container immersed in a 20° C. waterbath. Each composition was mixed for 3 minutes and the compositions werecooled sufficiently to allow the thickeners to solidify. CompositionComponent A B C D Amount (grams) Unithox 450¹ 0.18 0.35 0.53 0.70Kemester 9022 0.70 0.53 0.35 0.18 Incroquat DBM-90 0.13 0.13 0.13 0.13(90% solution in ethanol) Ethanol:water 70:30 49.00  49.00  49.00 49.00  Tm (° C.) 47 47-50 47-50 42

[0261] All four formulations formed viscous compositions. Formula B wasmore translucent and gel-like than A. Formulation D appeared lessviscous. The melt temperatures were higher at ratios of Unithox450:Kemester 9022 of 0.66 to 1.5 but were fairly high for allformulations.

Example 27 Polyethoxylated Alcohol/Ester/Quaternary Amine ThickenerSystem

[0262] The following thickener systems were prepared according to theprocedure of Example 26: Composition Component A B C D Amount (grams)Abil 2440 0.18 0.35 0.53 0.70 Kemester 9022 0.70 0.53 0.34 0.18Incroquat DBM-90 0.13 0.13 0.13 0.13 Ethanol:water 68:32 49.00  49.00 49.00  49.00 

[0263] Formulation A produced a stable thick creamy composition having aTm of 44-45° C. Formulations B and C were quite low in viscosity andFormulation D showed almost no increase in viscosity.

Example 28 Alkylene Alcohol/Ester/Quaternary Amine Thickener System

[0264] The following thickener systems were prepared according to theprocedure of Example 26 except that the composition was homogenized foronly 15 seconds. Formulation Component A B C D Amount (grams) Novol 1.080.81 0.54 0.27 Kemester 9022 0.27 0.54 0.81 1.08 Incroquat DBM-90 0.250.25 0.25 0.25 Ethanol:water 60:40 43.40 43.40 43.40 43.40 Viscosity(cps) unstable low 125,000 340,000

[0265] Formulation A was unstable and showed significant phaseseparation. Formulation B was homogenous and had very low viscosity.Formulation C was a viscous cream but showed some syneresis on standing.Formulation D was opaque and gel-like with a high viscosity and showedonly a slight amount of syneresis.

Example 29 Alkylene Alcohol/Ester/Amine Oxide Thickener System

[0266] The following thickener systems were prepared according to theprocedure of Example 28. Formulation Component A B C D Amount (grams)Novol 1.08 0.81 0.54 0.27 Kemester 9022 0.27 0.54 0.81 1.08 IncromineOxide B30P 1.80 1.80 1.80 1.80 Ethanol:water 60:40 41.85 41.85 41.8541.85 Viscosity (cps) 1,750 15,700 40,800 65,400

[0267] Composition A was translucent, fairly elastic and low inviscosity. Composition B was translucent, pearlescent, and fairlyelastic but significantly more viscous then composition A. CompositionsC and D were pearlescent, slightly opaque, and fairly elastic withhigher viscosities.

Example 30 Alkyl Phospholipid/Polyethoxylated Alkyl Alcohol ThickenerSystem

[0268] The following thickener systems were prepared according to theprocedure of Example 28. Formulation Component A B C D E F G H Amount(grams) Phospholipid SV¹ (35% 1.08 0.81 0.54 0.27 solution in water)Behenylphospholipid² 2.7 2.03 1.35 0.68 (40% solution in water) NikkolBB-5 0.27 0.54 0.81 1.08 0.27 0.54 0.81 1.08 Ethanol:water 60:40 43.6543.65 43.65 43.65 Ethanol 25.72 25.84 25.96 26.07 Water 16.31 16.6016.88 17.17 Viscosity (cps) <100 <100 6,170 4,590 <100 <100 6,300 29,400Viscosity (cps) post 9,000 12,400 6,400 37,200 CHG Addition

[0269] Samples A , B, E and F were uniform and stable but had lowviscosity. Samples C, D, G, and H were opaque and pearlescent withhigher viscosity values. CHG was added as a 20% solution in water to afinal concentration of 0.5% by weight to formulations C, D, G, and H.The viscosity was measured one day after adding CHG. The resultsindicate that the thickener systems are tolerant to CHG addition andthat addition of CHG may actually increase the viscosity for thesesystems. It should be noted that Phospholipid SV, like many single longchain quaternary amine-containing surfactants, is reported to havesignificant antimicrobial activity.

Example 31 Alkyl Betaine/Polyethoxylated Alkyl Alcohol Thickener System

[0270] The following formulations systems were prepared according to theprocedure of Example 28. After measuring the viscosity, CHG was added asa 20% solution to a final concentration of 0.5% by weight. The viscositywas measured again one day later. Formulation Component A B C D Amount(grams) Incronam B-40¹ (40% solution in 2.70 2.03 1.35 0.68 water)Nikkol BB-5 0.27 0.54 0.81 1.08 Ethanol:water 60:40 42.03 42.44 42.8243.25 Viscosity (cps) 40,700 52,600 52,500 35,300 Viscosity (cps)post-CHG 52,000 54,500 54,000 38,000 Addition

[0271] Formulations C and D were similar but were more elastic. Allformulations were homogenous after adding CHG and the CHG actuallyincreased the viscosity of the formulations.

Example 32 Hydroxyfunctional Ester Containing Thickener Systems

[0272] Behenyl Lactate was prepared by reacting methyl lactate (AldrichChemical Company, Inc. of Milwaukee, Wis.) with Lanette 22 (behenylalcohol, 90%, Henkel Corp. of Ambler, PA) in a transesterificationreaction according to the following method: 0.2 g sodium hydride (60% inmineral oil) was added to 32.6 grams Lanette 22 at 70° C. in a 3-neck250 ml glass flask purged with nitrogen and inserted with overheadstirrer, Dean Stark trap, thermometer, and condenser. To this was slowlyadded 9.4 g of methyl lactate and the contents were slowly heated to160° C. and held at that temperature for one hour. At this temperatureover 2 ml of methanol was collected. The contents were heated to 200° C.with a nitrogen sweep to remove any volatile components. Afterapproximately 15 minutes at 200° C. the contents were cooled. Uponcooling the product crystallized and had a melting point ofapproximately 57° C.

[0273] The following thickener systems were prepared includingsubsequent addition of CHG as described in Example 31. FormulationComponent A B C D E F Amount (grams) Behenyl lactate 1.08 0.81 0.54 0.271.08 0.81 Nikkol BB-5 0.27 0.54 0.81 1.08 Lanette 22 0.27 0.54 IncroquatDBM90 (90% in 0.25 0.25 isopropyl alcohol) Ethanol:water 60:40 43.6543.65 43.65 43.65 43.40 43.40 Viscosity (cps) 3,300 122,000 90,70096,000 164,000 206,000 Viscosity (cps) post CHG 875 92,500 76,300 71,500188,000 193,000 addition Formulation Component G H I J K L Amount(grams) Behenyl lactate 0.54 0.27 1.08 0.81 0.54 0.27 Nikkol BB-5Lanette 22 0.81 1.08 Incroquat DBM90 (90% in 0.25 0.25 0.30 0.60 0.901.20 isopropyl alcohol) Ethanol:water 60:40 43.40 43.40 43.62 43.5943.56 43.53 Viscosity (cps) 205,000 306,000 190,000 255,000 306,000128,000 Viscosity (cps) post CHG 207,000 214,000 207,000 256,000 266,000233,000 addition

[0274] The results show that behenyl lactate is a useful emulsifier forthe purposes of the present invention. Behenyl lactate forms homogenoushigh viscosity emulsions in a variety of systems over a broad range ofthickener ratios. Although sample A was low in viscosity, Samples B-Dformed very pearlescent viscoelastic compositions. Samples E-L formedvery viscous gel-like compositions. The compositions are also stable toCHG addition.

Example 33 Alkylene Monoglyceride/Ester/Amine Oxide Thickener System

[0275] The following thickener systems were prepared by heatingseparately the solvent and the thickener system to 75° C. The solventwas added to the thickener system rapidly followed by homogenization ona Silverson L4R at maximum speed for 15 seconds followed by stirringwith an overhead paddle stirrer in a glass container immersed in a 5-10°C. water bath. Each composition was mixed for 3 minutes after which thecomposition cooled sufficiently for the emulsifiers to solidify. Theviscosity was measured as described above. To each sample was then addedCHG as a 20% solution in water to a final concentration of 0.5% byweight. The CHG was mixed in well using a spatula and the sample wasallowed to equilibrate for 24 hours. The viscosity was then measuredagain. Composition Component A B C D Amount (grams) Glycerolmonoeurucate¹ 1.20 0.90 0.60 0.30 Kemester 9022 0.27 0.54 0.81 1.08Incroquat DBM-90 0.25 0.25 0.25 0.25 Ethanol:water 60:40 43:28 43:3143:34 43:37 Viscosity (cps)   630 105,000 149,000 173,000 Viscosity(cps) post CHG 9,200 110,000 205,000 202,000 addition

[0276] Composition A was bluish translucent but had a low viscosity.Composition B was similar to A but much more viscous than Composition A.Composition C was semi-opaque and even more viscous than Composition B.Sample D was opaque white with a fairly high viscosity.

Example 34 Viscosity as a Function of Shear Rate

[0277] The following example illustrates the pseudoplastic rheology andshear sensitivity of the compositions of the present invention. Theviscosity was measured as a function of shear rate using a RheometricsDyanamic Analyzer (RDA-II) with a 25 mm cone/plate fixture with a coneangle of 0.1 rad at a temperature of 25° C. Entrapped air was removedfrom the samples prior to testing by centrifugation. The viscosity wasmeasured in steady shear by keeping the rate of rotation constant. Thiswas done over a shear rate range of 0.06-40 per second. The samples usedfor this testing were prepared according to Example 1, Sample A (Brij78) and Example 32, Sample B. The following results were obtained:Viscosity (cps) Shear Rate Ex.1, Sample A Ex. 32, Sample B BrookfieldLVDV−I+ 294000 92500 0.06 Rheometrics  42000  7200 0.10 Rheometrics 37000  5700 1.0 Rheometrics  14000  2300 3.0 Rheometrics  3800  68010.0 Rheometrics  2100  420 40.0 Rheometrics   720  140

[0278] The results indicate that the viscosity is very shear sensitive.This allows the compositions to dispense well into the hand withoutrunning and yet allows the compositions to spread easily across the skinsurface.

Example 35 Foam Formulation

[0279] 90 g of the formulation of Example 25 was charged to a glasspressure vessel at room temperature. To this was added 7 g propane and 3g isobutane. The addition of the propellant resulted in a dramatic dropin viscosity. The viscosity appeared to be about the viscosity of water.The formulation appeared as a single emulsified opaque white liquid.After sitting for several days the propellant formed a separate phasebut was easily reemulsified by shaking. The formulation produced a whitefoam.

Example 36

[0280] This example demonstrates that monovalent salts of acids areuseful as co-emulsifiers in the present invention.

[0281] The samples were prepared according to the formulae outlined inthe table below by placing all components in a 4-oz. jar. The jar wascapped and heated to 65° C. until all components were dissolved. The jarwas then swirled to mix the components, removed from the heat andallowed to cool to ambient temperature. Viscosity measurements weretaken as identified in the table. Separation tests were done as outlinedin Example 3. Sample A B Component Amount (grams) BB-5 0.96 0.96 SodiumStearate 0.36 0.96 190 Ethanol 42.00 41.60 Deionized Water 16.70 16.50Viscosity (cps) 5,904¹ 320,000² % Separation (by Volume) 0 0

Example 37 Alkyl Alcohol/Long Chain Polyethoxylate/Quaternary AmineThickener System

[0282] The following formulation was prepared using the compounds listedbelow in the percentages indicated. Ingredient Number Ingredient wt.Percent Part A  1 Beheneth Ether (BB-10)¹ 1.08  2Dibehenyldimethylammonium 0.25 methosulfate²  3 Behenyl Alcohol³ (BE-22)0.67 Part B  4 Diisopropyl Dimerate⁴ 1.50  5 Squalane⁵ 1.50  6Dimethicone L45/350⁶ 0.50 Part C  7 Polyethylene Glycol 900⁷ 1.26  8Polyethylene Glycol 600⁸ 0.54  9 Glycerol⁹ 0.72 10 Water 25.11 11 EthylAlcohol 61.86 12 Chlorhexidine¹⁰ Gluconate solution 5.00

[0283] A total batch size of 500 g of the composition was prepared byplacing the ingredients of Parts A and B into a sealed one quart glassjar followed by heating to 90° C. until all components were melted(about 75 min.). The ingredients of Part C along with the water wereplaced into a one 200 ml glass jar and heated to 90° C. (also about 75min.) Part C was added to the Part A/B molten mixture and homogenizedusing the Silverson homogenizer at full speed for 60 seconds. This wassealed and heated at 56° C. for approximately 1 hour and then allowed tocool on a roller. Once cooled the ethanol was added followed by sealingand shaking the contents vigorously for 60 seconds until the sample washomogenous. The contents were once again sheared on the homogenizer atfull speed for 60 seconds followed by vigorous shaking for 20 secondsand repeat homogenization for 60 seconds.

[0284] This formula was applied by numerous volunteers and found to havevery nice cosmetic properties.

[0285] While in accordance with the patent statutes, description of thepreferred weight fractions, processing conditions, and product usageshave been provided, the scope of the invention is not intended to belimited thereto or thereby. Various modifications and alterations of thepresent invention will be apparent to those skilled in the art withoutdeparting from the scope and spirit of the present invention. TheExamples described in this application are illustrative of thepossibilities of varying the type, quantity and ratio of composition aswell as the methods for making formulations of the present invention.The complete disclosures of all patents, patent applications, andpublications recited herein are incorporated by reference, as ifindividually incorporated by reference.

What is claimed is:
 1. A method of maintaining or improving skincondition, the method comprising applying to skin a compositioncomprising: a) a lower alcohol and water in a weight ratio of about35:65 to about 95:5; and b) a thickener system present in an amount ofabout 0.5% by weight to about 8% by weight, based on the total weight ofthe composition; wherein the thickener system comprises at least twosolid emulsifiers, each in an amount of at least about 0.05% by weight,based on the total weight of the composition; wherein at least oneemulsifier comprises: (i) at least one hydrophobic group selected fromthe group consisting of: (A) an alkyl group of at least 16 carbon atoms;(B) an alkenyl group of at least 16 carbon atoms; and (C) an aralkyl oran aralkenyl group of at least 20 carbon atoms; and (ii) at least onehydrophilic group selected from the group consisting of: (A) an amidegroup; (B) a short chain ester of a long chain alcohol or acid; (C) apolyglucoside group having 1-10 glucose units; (D) a polyglycerol estergroup having 1-15 glycerol units; (E) a secondary amine group; (F) atertiary amine group; (G) a quaternary amine group; (H) an anionicgroup; (I) a zwitterionic group; and (J) combinations of these groups;wherein the composition has a viscosity of at least about 4,000centipoise at 23° C. in the absence of auxiliary thickeners.
 2. Themethod of claim 1 wherein the thickener system further comprises atleast one emulsifier having: (i) at least one hydrophobic group selectedfrom the group consisting of: (A) an alkyl group of at least 16 carbonatoms; (B) an alkenyl group of at least 16 carbon atoms; and (C) anaralkyl or an aralkenyl group of at least 20 carbon atoms; and (ii) atleast one hydrophilic group selected from the group consisting of: (A)an ethylene oxide- and/or propylene oxide-containing group, which isbonded to the hydrophobic group through an ether or ester bond andoptionally terminated with a (C1-C36)alkyl ester, (C2-C36)alkenyl ester,or (C6-C36)alkaryl ester; (B) an alcohol group; (C) a polyhydric alcoholgroup; (D) an ester or ether group of a polyhydric alcohol orpolyalkoxylated derivative thereof; (E) an ester or ether group ofsorbitan or polyalkoxylated derivative thereof; and (F) combinations ofthese groups.
 3. The method of claim 1 wherein the composition does notseparate by more than about 10% by volume when centrifuged for 30minutes at 2275× g.
 4. The method of claim 1 wherein the hydrophobic andhydrophilic groups are selected to provide a thickener system having aweight average hydrophile/lipophile balance of about 8 to about
 12. 5.The method of claim 1 wherein the composition further comprises at leastone emollient distinct from the thickener system.
 6. The method of claim1 wherein the composition further comprises an antimicrobial agentdistinct from the lower alcohol.
 7. The method of claim 1 wherein thecomposition further comprises a stabilizer.
 8. The method of claim 1wherein the composition further comprises a therapeutic agent.
 9. Themethod of claim 1 wherein the lower alcohol and water are present in aweight ratio of about 60:40 to about 75:25.
 10. The method of claim 1wherein the thickener system comprises one or more emulsifiers capableof forming an alcoholic composition having a viscosity of at least about10,000 centipoise at 23° C. in the absence of a auxiliary thickener. 11.The method of claim 1 wherein the composition has a viscosity of about80,000 centipoise to about 500,000 centipoise at 23° C. in the absenceof an auxiliary thickener.
 12. The method of claim 1 wherein the amidegroup has the structure —NHC(O)R′″ or —C(O)NHR′″, wherein R′″ ishydrogen or an alkyl group of 1-10 carbon atoms optionally substitutedwith N, O, or S atoms.
 13. The method of claim 1 wherein the anionicgroup is selected from the group consisting of a sulfate, a sulfonate, aphosphate, a phosphonate, and a carboxylate group.
 14. The method ofclaim 1 wherein the zwitterionic group has the formula:

wherein: each R″ is independently hydrogen, an alkyl group, an alkenylgroup, an alkyl carboxyl group, or an alkenyl carboxyl group, whichalkyl or alkenyl groups are optionally substituted with N, O, or Satoms; Q is hydrogen or hydroxyl; x is 1 to 4; and L′ is —CO₂ ⁻,—OP(O)(O⁻)(O^(−M) ⁺), —(O)P(OR′″)(O)(O⁻), —SO₂O⁻, or —OSO₂O⁻ wherein:R′″ is hydrogen or an alkyl group of 1-10 carbon atoms optionallysubstituted with N, O, or S atoms; M⁺ is a positively charged counterionpresent in a molar ratio necessary to achieve a net neutral charge onthe emulsifier and is selected from the group consisting of hydrogen,sodium, potassium, lithium, ammonium, calcium, magnesium, and N⁺R″₄. 15.A method of maintaining or improving skin condition, the methodcomprising applying to skin a composition comprising: a) a lower alcoholand water in a weight ratio of about 35:65 to about 95:5; b) a thickenersystem present in an amount of about 0.5% by weight to about 8% byweight, based on the total weight of the composition; wherein thethickener system comprises at least two emulsifiers, each in an amountof at least about 0.05% by weight, based on the total weight of thecomposition; wherein at least one emulsifier comprises: (i) at least onehydrophobic group selected from the group consisting of: (A) an alkylgroup of at least 16 carbon atoms; (B) an alkenyl group of at least 16carbon atoms; and (C) an aralkyl or an aralkenyl group of at least 20carbon atoms; and (ii) at least one hydrophilic group selected from thegroup consisting of: (A) an amide group; (B) a short chain ester of along chain alcohol or acid; (C) a polyglucoside group having 1-10glucose units; (D) a polyglycerol ester group having 1-15 glycerolunits; (E) a secondary amine group; (F) a tertiary amine group; (G) aquaternary amine group; (H) an anionic group; (I) a zwitterionic group;and (J) combinations of these groups; and wherein at least oneemulsifier comprises: (i) at least one hydrophobic group selected fromthe group consisting of: (A) an alkyl group of at least 16 carbon atoms;(B) an alkenyl group of at least 16 carbon atoms; and (C) an aralkyl oran aralkenyl group of at least 20 carbon atoms; and (ii) at least onehydrophilic group selected from the group consisting of: (A) an ethyleneoxide- and/or propylene oxide-containing group, which is bonded to thehydrophobic group through an ether or ester bond and optionallyterminated with a (C1-C36)alkyl ester, (C2-C36)alkenyl ester, or(C6-C36)alkaryl ester; (B) an alcohol group; (C) a polyhydric alcoholgroup; (D) an ester or ether group of a polyhydric alcohol orpolyalkoxylated derivative thereof; (E) an ester or ether group ofsorbitan or polyalkoxylated derivative thereof; and (F) combinations ofthese groups; and c) an antimicrobial agent distinct from the loweralcohol; wherein the composition has a melt temperature of greater thanabout 35° C. and the at least two emulsifiers provide the compositionwith a viscosity of at least about 4,000 centipoise at 23° C. in theabsence of an auxiliary thickener.
 16. A method of maintaining orimproving skin condition, the method comprising applying to skin acomposition comprising: a) a lower alcohol and water in a weight ratioof about 35:65 to about 95:5; and b) a thickener system present in anamount of about 0.5% by weight to about 8% by weight, based on the totalweight of the composition; wherein the thickener system comprises atleast two emulsifiers, wherein at least one of the emulsifiers is solidat ambient temperature and each is present in an amount of at leastabout 0.05% by weight, based on the total weight of the composition;wherein at least one emulsifier comprises: (i) at least one hydrophobicgroup selected from the group consisting of: (A) an alkyl group of atleast 16 carbon atoms; (B) an alkenyl group of at least 16 carbon atoms;and (C) an aralkyl or an aralkenyl group of at least 20 carbon atoms;and (ii) at least one hydrophilic group selected from the groupconsisting of: (A) an amide group; (B) a short chain ester of a longchain alcohol or acid; (C) a polyglucoside group having 1-10 glucoseunits; (D) a polyglycerol ester group having 1-15 glycerol units; (E) asecondary amine group; (F) a tertiary amine group; (G) a quaternaryamine group; (H) an anionic group; (I) a zwitterionic group; and (J)combinations of these groups; wherein the composition has a viscosity ofat least about 4,000 centipoise at 23° C. in the absence of auxiliarythickeners.
 17. The method of claim 16 wherein the thickener systemfurther comprises at least one emulsifier having: (i) at least onehydrophobic group selected from the group consisting of: (A) an alkylgroup of at least 16 carbon atoms; (B) an alkenyl group of at least 16carbon atoms; and (C) an aralkyl or an aralkenyl group of at least 20carbon atoms; and (ii) at least one hydrophilic group selected from thegroup consisting of: (A) an ethylene oxide- and/or propyleneoxide-containing group, which is bonded to the hydrophobic group throughan ether or ester bond and optionally terminated with a (C1-C36)alkylester, (C2-C36)alkenyl ester, or (C6-C36)alkaryl ester; (B) an alcoholgroup; (C) a polyhydric alcohol group; (D) an ester or ether group of apolyhydric alcohol or polyalkoxylated derivative thereof; (E) an esteror ether group of sorbitan or polyalkoxylated derivative thereof; and(F) combinations of these groups.
 18. The method of claim 17 wherein thecomposition does not separate by more than about 10% by volume whencentrifuged for 30 minutes at 2275× g.
 19. The method of claim 17wherein the hydrophobic and hydrophilic groups are selected to provide athickener system having a weight average hydrophile/lipophile balance ofabout 8 to about
 12. 20. The method of claim 16 wherein the compositionfurther comprises at least one emollient distinct from the thickenersystem.
 21. The method of claim 16 wherein at least one emulsifier is inthe form of a liquid.
 22. The method of claim 16 wherein the compositionfurther comprises an antimicrobial agent distinct from the loweralcohol.
 23. The method of claim 16 wherein the composition furthercomprises a stabilizer.
 24. The method of claim 16 wherein thecomposition further comprises polydimethylsiloxane or derivativesthereof selected from the group consisting of polyether polysiloxanecopolymers, polyalkyl siloxanes, polyaryl/alkyl/siloxanes, polysiloxanepolyalkylene copolymers, and dialkoxy dimethyl siloxanes.
 25. The methodof claim 16 wherein the composition further comprises a therapeuticagent.
 26. The method of claim 16 wherein at least one emulsifier isselected from the group consisting of an alkyl polyglucoside, an alkenylpolyglucoside, a C₁-C₄ alkyl or alkenyl ester of a long chain alkyl oralkenyl alcohol, a C₁-C₄ ester of a long chain acid, a polyglycerolester, a quaternary amine, a tertiary amine and protonated saltsthereof, an amine oxide, a zwitterionic compound, an alkyl amide, analkenyl amide, an anionic compound, and mixtures thereof.
 27. The methodof claim 16 wherein the lower alcohol and water are present in a weightratio of about 60:40 to about 75:25.
 28. The method of claim 16 whereinthe thickener system comprises one or more emulsifiers capable offorming an alcoholic composition having a viscosity of at least about10,000 centipoise at 23° C. in the absence of an auxiliary thickener.29. The method of claim 16 wherein the composition has a viscosity ofabout 80,000 centipoise to about 500,000 centipoise at 23° C. in theabsence of an auxiliary thickener.
 30. The method of claim 16 whereinthe amide group has the structure —NHC(O)R′″ or —C(O)NHR′″, wherein R′″is hydrogen or an alkyl group of 1-10 carbon atoms optionallysubstituted with N, O, or S atoms.
 31. The method of claim 16 whereinthe anionic group is selected from the group consisting of a sulfate, asulfonate, a phosphate, a phosphonate, and a carboxylate group.
 32. Themethod of claim 16 wherein the zwitterionic group has the formula:

wherein: each R″ is independently hydrogen, an alkyl group, an alkenylgroup, an alkyl carboxyl group, or an alkenyl carboxyl group, whichalkyl or alkenyl groups are optionally substituted with N, O, or Satoms; Q is hydrogen or hydroxyl; x is 1 to 4; and L′ is —CO₂ ³¹ ,—OP(O)(O⁻)(O⁻M⁺), —(O)P(OR′″)(O)(O⁻), —SO₂O⁻, or —OSO₂O⁻ wherein: R′″ ishydrogen or an alkyl group of 1-10 carbon atoms optionally substitutedwith N, O, or S atoms; M⁺ is a positively charged counterion present ina molar ratio necessary to achieve a net neutral charge on theemulsifier and is selected from the group consisting of hydrogen,sodium, potassium, lithium, ammonium, calcium, magnesium, and N⁺R″₄. 33.A method of maintaining or improving skin condition, the methodcomprising applying to skin a composition comprising: a) a lower alcoholand water in a weight ratio of about 35:65 to about 95:5; and b) athickener system present in an amount of about 0.5% by weight to about8% by weight, based on the total weight of the composition; wherein thethickener system comprises at least two emulsifiers, wherein at leastone of the emulsifiers is solid at ambient temperature and each ispresent in an amount of at least about 0.05% by weight, based on thetotal weight of the composition; wherein at least one emulsifiercomprises: (i) at least one hydrophobic group selected from the groupconsisting of: (A) an alkyl group of at least 16 carbon atoms; (B) analkenyl group of at least 16 carbon atoms; and (C) an aralkyl or anaralkenyl group of at least 20 carbon atoms; and (ii) at least onehydrophilic group selected from the group consisting of: (A) an amidegroup; (B) a short chain ester of a long chain alcohol or acid; (C) apolyglucoside group having 1-10 glucose units; (D) a polyglycerol estergroup having 1-15 glycerol units; (E) combinations of these groups;wherein the composition has a viscosity of at least about 4,000centipoise at 23° C. in the absence of auxiliary thickeners.
 34. Amethod of maintaining or improving skin condition, the method comprisingapplying to skin a composition comprising: a) a lower alcohol and waterin a weight ratio of about 35:65 to about 95:5; and b) a thickenersystem present in an amount of about 0.5% by weight to about 8% byweight, based on the total weight of the composition; wherein thethickener system comprises at least two emulsifiers, wherein at leastone of the emulsifiers is solid at ambient temperature and each ispresent in an amount of at least about 0.05% by weight, based on thetotal weight of the composition; wherein at least one emulsifiercomprises: (i) at least one hydrophobic group selected from the groupconsisting of: (A) an alkyl group of at least 16 carbon atoms; (B) analkenyl group of at least 16 carbon atoms; and (C) an aralkyl or anaralkenyl group of at least 20 carbon atoms; and (ii) at least onehydrophilic group selected from the group consisting of: (A) an amidegroup; (B) a short chain ester of a long chain alcohol or acid; (C) apolyglucoside group having 1-10 glucose units; (D) a polyglycerol estergroup having 1-15 glycerol units; (E) a secondary amine group; (F) atertiary amine group; (G) a quaternary amine group; (H) an anionicgroup; (I) a zwitterionic group; and (J) combinations of these groups;wherein the composition has a viscosity of at least about 4,000centipoise at 23° C. in the absence of auxiliary thickeners.
 35. Amethod of delivering a fragrance to skin, the method comprising:applying to skin a composition comprising: a) a fragrance; and b) alower alcohol and water in a weight ratio of about 35:65 to about 95:5;and c) a thickener system present in an amount of about 0.5% by weightto about 8% by weight, based on the total weight of the composition;wherein the thickener system comprises at least two solid emulsifiers,each in an amount of at least about 0.05% by weight, based on the totalweight of the composition; wherein at least one emulsifier comprises:(i) at least one hydrophobic group selected from the group consistingof: (A) an alkyl group of at least 16 carbon atoms; (B) an alkenyl groupof at least 16 carbon atoms; and (C) an aralkyl or an aralkenyl group ofat least 20 carbon atoms; and (ii) at least one hydrophilic groupselected from the group consisting of: (A) an amide group; (B) a shortchain ester of a long chain alcohol or acid; (C) a polyglucoside grouphaving 1-10 glucose units; (D) a polyglycerol ester group having 1-15glycerol units; (E) a secondary amine group; (F) a tertiary amine group;(G) a quaternary amine group; (H) an anionic group; (I) a zwitterionicgroup; and (J) combinations of these groups; b) wherein the compositionhas a viscosity of at least about 4,000 centipoise at 23° C. in theabsence of auxiliary thickeners.
 36. The method of claim 35 wherein thethickener system further comprises at least one emulsifier having: (i)at least one hydrophobic group selected from the group consisting of:(A) an alkyl group of at least 16 carbon atoms; (B) an alkenyl group ofat least 16 carbon atoms; and (C) an aralkyl or an aralkenyl group of atleast 20 carbon atoms; and (ii) at least one hydrophilic group selectedfrom the group consisting of: (A) an ethylene oxide- and/or propyleneoxide-containing group, which is bonded to the hydrophobic group throughan ether or ester bond and optionally terminated with a (C1-C36)alkylester, (C2-C36)alkenyl ester, or (C6-C36)alkaryl ester; (B) an alcoholgroup; (C) a polyhydric alcohol group; (D) an ester or ether group of apolyhydric alcohol or polyalkoxylated derivative thereof; (E) an esteror ether group of sorbitan or polyalkoxylated derivative thereof; and(F) combinations of these groups.
 37. A method of delivering a fragranceto skin, the method comprising: applying to skin a compositioncomprising: a) a fragrance; and b) a lower alcohol and water in a weightratio of about 35:65 to about 95:5; and c) a thickener system present inan amount of about 0.5% by weight to about 8% by weight, based on thetotal weight of the composition; wherein the thickener system comprisesat least two emulsifiers, wherein at least one of the emulsifiers issolid at ambient temperature and each is present in an amount of atleast about 0.05% by weight, based on the total weight of thecomposition; wherein at least one emulsifier comprises: (i) at least onehydrophobic group selected from the group consisting of: (A) an alkylgroup of at least 16 carbon atoms; (B) an alkenyl group of at least 16carbon atoms; and (C) an aralkyl or an aralkenyl group of at least 20carbon atoms; and (ii) at least one hydrophilic group selected from thegroup consisting of: (A) an amide group; (B) a short chain ester of along chain alcohol or acid; (C) a polyglucoside group having 1-10glucose units; (D) a polyglycerol ester group having 1-15 glycerolunits; (E) a secondary amine group; (F) a tertiary amine group; (G) aquaternary amine group; (H) an anionic group; (I) a zwitterionic group;and (J) combinations of these groups; wherein the composition has aviscosity of at least about 4,000 centipoise at 23° C. in the absence ofauxiliary thickeners.